Dual angiopoietin-2 and VEGFA inhibition elicits antitumor immunity that is enhanced by PD-1 checkpoint blockade

Inhibition of VEGF signaling prevents exhaustion and enhances anti-leukemia efficacy of CAR-T cells via Wnt/β-catenin pathway

BACKGROUND

Current challenges in Chimeric Antigen Receptor (CAR) -T cell therapy for hematological cancers include T cell exhaustion and limited persistence, which contribute to cancer relapse.

METHODS

The effects of Axitinib, a VEGFR inhibitor, on the biological functions of CAR-T cells in vitro and in vivo were investigated by comparing CAR-T cells pre-treated ex vivo with Axitinib, as well as utilizing a B-ALL mouse model. Real-time quantitative PCR and Western blotting were employed to detect the expression of molecules related to differentiation, exhaustion, and the Wnt pathway in CAR-T cells. Flow cytometry was used to assess changes in CAR-T cell differentiation, exhaustion, activation, apoptosis, proliferation, and cytokine secretion. Western blotting and flow cytometry were used to assess changes in VEGFR expression. Bioluminescence imaging, flow cytometry, and immunohistochemistry (IHC) analysis were used to evaluate changes in tumor burden in mice receiving different treatments, while hematoxylin and eosin (H&E) staining were used to monitor histological changes in the liver and spleen of mice.

RESULTS

Axitinib treatment notably reduced CAR-T cell exhaustion and terminal differentiation both under tonic signaling and tumor antigen exposure scenarios. Furthermore, CAR-T cells pretreated with Axitinib demonstrated enhanced anti-tumor efficacy and prolonged survival in vivo. Mechanistically, Axitinib treatment upregulated the Wnt/β-catenin signaling pathway in CAR-T cells. Using agonists/inhibitors of the Wnt/β-catenin pathway could respectively mimic or counteract the effects of Axitinib on CAR-T cell exhaustion and differentiation. CAR-T cells treated with Axitinib can inhibit the VEGFR2 pathway. CAR-T cells treated with anti-VEGFR2 antibody can activate the Wnt/β-catenin pathway and prevent CAR-T cell exhaustion.

CONCLUSION

Axitinib confers resistance to exhaustion in CAR-T cells by modulating the Wnt/β-catenin signaling pathway.

Tumor microenvironment-driven resistance to immunotherapy in non-small cell lung cancer: strategies for Cold-to-Hot tumor transformation

Non-small cell lung cancer (NSCLC) represents a formidable challenge in oncology due to its molecular heterogeneity and the dynamic suppressive nature of its tumor microenvironment (TME). Despite the transformative impact of immune checkpoint inhibitors (ICIs) on cancer therapy, the majority of NSCLC patients experience resistance, necessitating novel approaches to overcome immune evasion. This review highlights shared and subtype-specific mechanisms of immune resistance within the TME, including metabolic reprogramming, immune cell dysfunction, and physical barriers. Beyond well-characterized components such as regulatory T cells, tumor-associated macrophages, and myeloid-derived suppressor cells, emerging players - neutrophil extracellular traps, tertiary lymphoid structures, and exosomal signaling networks - underscore the TME's complexity and adaptability. A multi-dimensional framework is proposed to transform cold, immune-excluded tumors into hot, immune-reactive ones. Key strategies include enhancing immune infiltration, modulating immunosuppressive networks, and activating dormant immune pathways. Cutting-edge technologies, such as single-cell sequencing, spatial transcriptomics, and nanomedicine, are identified as pivotal tools for decoding TME heterogeneity and personalizing therapeutic interventions. By bridging mechanistic insights with translational innovations, this review advocates for integrative approaches that combine ICIs with metabolic modulators, vascular normalizers, and emerging therapies such as STING agonists and tumor vaccines. The synergistic potential of these strategies is poised to overcome resistance and achieve durable antitumor immunity. Ultimately, this vision underscores the importance of interdisciplinary collaboration and real-time TME profiling in refining precision oncology for NSCLC, offering a blueprint for extending these advances to other malignancies.

The role of innate immune cells in modulating vascular dynamics in skin malignancies

A developing tumor relies heavily on blood vessels to supply oxygen and nutrients. As a result, angiogenesis, the formation of new blood vessels, supports tumor growth and progression. Similarly, lymphangiogenesis, the formation of new lymphatic vessels, plays a critical role in metastatic dissemination by providing pathways for malignant cells to spread. The tumor microenvironment is crucial for establishing and maintaining these vascular networks, with innate immune cells playing a key regulatory role. Notably, immune cells are specifically enriched in barrier tissues, such as the skin, emphasizing their importance in skin malignancies. Therefore, understanding their role in regulating angiogenesis and lymphangiogenesis is essential for developing novel therapeutic strategies. This review article explores how innate immune cells influence tumor vasculature and highlights the therapeutic potential that may arise from this knowledge.

A single-cell atlas of bladder cancer unveils dynamic cellular composition and endothelial functional shifts during progression

PURPOSE

Bladder cancer (BC) is characterized by high heterogeneity, with non-muscle-invasive (NMIBC) and muscle-invasive (MIBC) stages differing significantly in clinical behavior and outcomes. The transition from NMIBC to MIBC involves extensive tumor microenvironment (TME) remodeling, particularly in endothelial cells (ECs), which drive angiogenesis and modulate immune and extracellular matrix (ECM) interactions. However, the precise roles of ECs in this progression remain poorly defined.

METHODS

Public single-cell RNA sequencing (scRNA-seq) datasets from 47 BC patients were analyzed to characterize endothelial cell heterogeneity and functional states across NMIBC and MIBC. Computational tools such as CellChat were applied to reconstruct cell-cell communication networks, focusing on pathways related to angiogenesis, immune crosstalk, and ECM remodeling.

RESULTS

Twelve major cell types were identified, with endothelial cells exhibiting distinct transcriptional profiles between NMIBC and MIBC. NMIBC-associated ECs promoted adhesion and migration through HMGB1 and CXCL12 signaling. In contrast, MIBC was enriched in an ADAM10+ endothelial subset associated with vascular remodeling and activation of Wnt signaling via CTNNB1. Key ligand-receptor interactions highlighted the dynamic roles of ECs in TME modulation during BC progression.

CONCLUSIONS

This study reveals stage-specific endothelial cell phenotypes and signaling networks in BC. The identification of an MIBC-specific ADAM10+ endothelial subset underscores its potential role in driving tumor progression and highlights opportunities for stage-adapted vascular-targeted therapies. These findings advance our understanding of BC pathogenesis and provide the foundation for novel therapeutic strategies.

Single-cell atlas of endothelial and mural cells across primary and metastatic brain tumors

Central nervous system (CNS) malignancies include primary tumors, such as gliomas, and brain metastases (BrMs) originating from diverse extracranial cancers. The blood-brain barrier (BBB) is a key structural component of both primary and metastatic brain cancers. Here, we comprehensively analyzed the two major BBB cell types, endothelial and mural cells, across non-tumor brain tissue, isocitrate dehydrogenase (IDH) mutant (IDH mut) low-grade gliomas, IDH wild-type (IDH WT) high-grade glioblastomas (GBMs), and BrMs from various primary tumors. Bulk and single-cell RNA sequencing, integrated with spatial analyses, revealed that GBMs, but not low-grade gliomas, exhibit significant alterations in the tumor vasculature, including the emergence of diverse pathological vascular cell subtypes. However, these alterations are less pronounced in GBMs than in BrMs. Notably, the BrM vasculature shows higher permeability and more extensive interactions with distinct immune cell populations. This vascular atlas presents a resource toward understanding of tumor-specific vascular features in the brain, providing a foundation for developing vascular- and immune-targeting therapies.

Angiogenesis and targeted therapy in the tumour microenvironment: From basic to clinical practice

Angiogenesis, as a core marker of cancer survival and growth, is integral to the processes of tumour growth, invasion and metastasis. In recent years, targeted angiogenesis treatment strategies have gradually become an important direction in cancer treatment. Single-cell sequencing technology can provide new insights into targeted angiogenesis by providing a deeper understanding of the heterogeneity of tumour endothelial cells and exploring the interactions between endothelial cells and surrounding cells in the tumour microenvironment. Here, we systematically review the research progress in endothelial cell pathophysiology and its endothelial‒mesenchymal transition and illustrate the heterogeneity of endothelial cells from a single-cell perspective. Finally, we examine the contributions of different cell types within the tumour microenvironment in relation to tumour angiogenesis, as well as the latest progress and strategies in targeted angiogenesis therapy, hoping to provide useful insights into the clinical application of antiangiogenic treatment. Furthermore, a summary of the present progress in the development of potential angiogenesis inhibitors and the ongoing clinical trials for combination therapies is provided. KEY POINTS: Angiogenesis plays a key role in tumour progression, invasion and metastasis, so strategies targeting angiogenesis are gradually becoming an important direction in cancer therapy. Interactions between endothelial cells and stromal cells and immune cells in the tumour microenvironment are significant in angiogenesis. The application of antiangiogenic immunotherapy and nanotechnology in antiangiogenic therapy provides a vital strategy for prolonging the survival of cancer patients.

Pipelines for lymphocyte homeostasis maintenance during cancer immunotherapy

In general, increasing lymphocyte entry into tumor microenvironment (TME) and limiting their efflux will have a positive effect on the efficacy of immunotherapy. Current studies suggest maintenance lymphocyte homeostasis during cancer immunotherapy through the two pipelines tumor-associated high endothelial venules and lymphatic vessels. Tumor-associated high endothelial venules (TA-HEVs) play a key role in cancer immunotherapy through facilitating lymphocyte trafficking to the tumor. While tumor-associated lymphatic vessels, in contrast, may promote the egress of lymphocytes and restrict their function. Therefore, the two traffic control points might be potential to maintain lymphocyte homeostasis in cancer during immunotherapy. Herein, we highlight the unexpected roles of lymphocyte circulation regulated by the two gateways for through reviewing the biological characters and functions of TA-HEVs and tumor-associated lymphatic vessels in the entry, positioning and exit of lymphocyte cells in TME during anti-tumor immunity.

Efficacy and safety of sintilimab plus bevacizumab and CAPOX as first-line treatment for patients with RAS-mutant, microsatellite stable, metastatic colorectal cancer

BACKGROUND

This research aimed to assess the efficacy and safety of combining sintilimab with bevacizumab, oxaliplatin, and capecitabine as a primary therapy for patients with RAS-mutated, microsatellite stable (MSS), and metastatic colorectal cancer (mCRC).

METHODS

In this prospective, open-label, single-arm, phase II trial, eligible patients received up to 8 cycles of capecitabine and oxaliplatin/bevacizumab plus sintilimab, followed by maintenance therapy with capecitabine, bevacizumab, and sintilimab every three weeks until disease progression. Treatment response was evaluated every 2 cycles (6 weeks) according to the Response Evaluation Criteria in Solid Tumors version 1.1. The primary endpoint was ORR, while the secondary endpoints included PFS and AEs.

RESULTS

The efficacy analysis and safety analysis included 33 patients. The overall response rate was 72.7%, and the median PFS in the full analysis set was 12.9 months (95% CI: 7.5-18.3), and median OS was not reached. Patients with liver metastases demonstrated a higher ORR (20/24 [83.3%]) than those without (4/9 [44.4%], p = 0.073), and the median PFS was 14.7 for patients with liver metastases and 9.6 months for those without (HR: 1.05, 95%CI: 0.34-3.24; p = 0.932). Most immune-related AEs had grades 1-2, and immunotherapy was discontinued in 4 patients due to immune-related AEs. No treatment-related deaths occurred during the study.

CONCLUSIONS

The therapeutic regimen showed encouraging antitumor effects and a favorable safety profile in patients with RAS mutations, MSS, and mCRC, yielding durable results throughout an extended follow-up duration, irrespective of the presence of liver metastases. This research is of great significance because it addresses the limited treatment options in the field of MSS mCRC patients. By providing new treatment strategies or methods, it brings more hope and choices to patients and offers valuable new insights and research directions to the medical community.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov: NCT06206096. Registered on May 26, 2021.

Profiling Multiple CD8+ T-cell Functional Dimensions Enhances Breast Cancer Immune Assessment

CD8+ T-cell abundance is insufficient to assess antitumor immunity and shows poor performance in predicting breast cancer prognosis and immunotherapy response, presumably owing to the complexity of CD8+ T-cell functionalities. Although single-cell RNA sequencing can dissect the multifaceted functions of CD8+ T cells for better immune assessment, its clinical application is limited. In this study, we developed bulk RNA sequencing-based FuncDimen models from integrative analysis of single-cell RNA sequencing and matched bulk RNA sequencing data to evaluate CD8+ T-cell functionalities across five dimensions: tumor reactivity, cytotoxicity, IFNγ secretion, proliferation, and apoptosis. The FuncDimen models quantifying different functional dimensions of CD8+ T cells were validated in our breast cancer cohort and external databases using immunofluorescence and imaging mass cytometry. We calculated the FuncAggre score by weighted aggregation of all five FuncDimen models to encapsulate the overall antitumor immunity. In our breast cancer cohort and external databases, the FuncAggre score demonstrated superior predictive performance for breast cancer prognosis (time-dependent AUC: 0.56-0.70) and immunotherapy response (AUC: 0.71-0.83) over other immune biomarkers, regardless of the breast cancer molecular subtype. Together, the FuncDimen models offer a refined assessment of antitumor immunity mediated by CD8+ T cells in the clinic, enhancing prognostic prediction and aiding personalized immunotherapy in breast cancer.

Intratumoral Collagen Deposition Supports Angiogenesis Suggesting Anti-angiogenic Therapy in Armored and Cold Tumors

A previous study classifies solid tumors based on collagen deposition and immune infiltration abundance, identifying a refractory subtype termed armored & cold tumors, characterized by elevated collagen deposition and diminished immune infiltration. Beyond its impact on immune infiltration, collagen deposition also influences tumor angiogenesis. This study systematically analyzes the association between immuno-collagenic subtypes and angiogenesis across diverse cancer types. As a result, armored & cold tumors exhibit the highest angiogenic activity in lung adenocarcinoma (LUAD). Single-cell and spatial transcriptomics reveal close interactions and spatial co-localization of fibroblasts and endothelial cells. In vitro experiments demonstrate that collagen stimulates tumor cells to express vascular endothelial growth factor A (VEGFA) and directly enhances vessel formation and endothelial cell proliferation through sex determining region Y box 18 (SOX18) upregulation. Collagen inhibition via multiple approaches effectively suppresses tumor angiogenesis in vivo. In addition, armored & cold tumors display superior responsiveness to anti-angiogenic therapy in advanced LUAD cohorts. Post-immunotherapy resistance, the transformation into armored & cold tumors emerges as a potential biomarker for selecting anti-angiogenic therapy. In summary, collagen deposition is shown to drive angiogenesis across various cancers, providing a novel and actionable framework to refine therapeutic strategies combining chemotherapy with anti-angiogenic treatments.

Sequential immunotherapy and bevacizumab treatments in glioblastoma multiforme: A case series and review of the literature

Glioblastoma multiforme (GBM) is a tumor with a high refractory rate to immunotherapy and a low tumor mutational burden phenotype, leading to limited immunogenic neoantigens. The present study aimed to investigate the sequential use of immunotherapy and bevacizumab in patients with GBM, exploring the clinical outcomes and potential complications. Patients received various combinations of immunotherapy and bevacizumab after standard treatment, including surgery, radiotherapy and temozolomide. Clinical courses, radiological findings and treatment outcomes were monitored and documented during each clinical visit through routine physical examinations, imaging studies and review of medical records. The efficacy and side effects of this sequential drug approach remained unclear. The common features of these patients were a marked decline in cognitive function and clinical deterioration, assessed clinically in the absence of obvious tumor progression. Radiological evaluation was also performed, particularly for possible cerebrovascular events. In these cases, the potential for sequential treatment to suppress tumors while inducing cerebrovascular events was also investigated, and patients were not lost to overt tumor progression. Notably, further research is required to clarify the mechanisms of action and complications associated with the sequential use of immunotherapy and bevacizumab in the treatment of GBM.

Enhancing Colorectal Cancer Treatment Through VEGF/VEGFR Inhibitors and Immunotherapy

OPINION STATEMENT

Colorectal cancer, ranking as the third most prevalent malignancy globally, substantially benefits from both immunotherapy and VEGF/VEGFR inhibitors. Nevertheless, the use of monotherapy proves inadequate in effectively tackling the heterogeneity of tumors and the intricacies of their microenvironment, frequently leading to drug resistance and immune evasion. This situation underscores the pressing need for innovative strategies aimed at augmenting the effectiveness and durability of treatments. Clinical research demonstrates that the combination of VEGF/VEGFR inhibitors (primarily including VEGF/VEGFR-targeted drugs and multi-kinase inhibitors) with immune checkpoint inhibitors creates a synergistic effect in the treatment of colorectal cancer. Our analysis explores how VEGF/VEGFR inhibitors recalibrate the tumor microenvironment, modulate immune cell functions, and influence the expression of immune checkpoints and cytokines. Furthermore, we critically evaluate the preclinical and clinical feasibility of these combined therapeutic approaches. Despite the potential for toxicity, the significant benefits and prospective applications of these strategies warrant thorough exploration. Exploring the synergistic mechanisms of these combined treatments has the potential to inaugurate a new paradigm in oncology, enabling more personalized and efficacious treatment modalities. Additionally, the synergy between VEGF/VEGFR inhibitors and nascent immunotherapies emerges as a promising field of inquiry.

Towards understanding cancer dormancy over strategic hitching up mechanisms to technologies

Delving into cancer dormancy has been an inherent task that may drive the lethal recurrence of cancer after primary tumor relief. Cells in quiescence can survive for a short or long term in silence, may undergo genetic or epigenetic changes, and can initiate relapse through certain contextual cues. The state of dormancy can be induced by multiple conditions including cancer drug treatment, in turn, undergoes a life cycle that generally occurs through dissemination, invasion, intravasation, circulation, immune evasion, extravasation, and colonization. Throughout this cascade, a cellular machinery governs the fate of individual cells, largely affected by gene regulation. Despite its significance, a precise view of cancer dormancy is yet hampered. Revolutionizing advanced single cell and long read sequencing through analysis methodologies and artificial intelligence, the most recent stage in the research tool progress, is expected to provide a holistic view of the diverse aspects of cancer dormancy.

Promotion Mechanisms of Stromal Cell-Mediated Lung Cancer Development Within Tumor Microenvironment

Lung cancer, with its high incidence and mortality rates, has garnered significant attention in the medical community. The tumor microenvironment (TME), composed of tumor cells, stromal cells, extracellular matrix, surrounding blood vessels, and other signaling molecules, plays a pivotal role in the development of lung cancer. Stromal cells within the TME hold potential as therapeutic targets for lung cancer treatment. However, the precise and comprehensive mechanisms by which stromal cells contribute to lung cancer progression have not been fully elucidated. This review aims to explore the mechanisms through which stromal cells in the tumor microenvironment promote lung cancer development, with a particular focus on how immune cells, tumor-associated fibroblasts, and endothelial cells contribute to immune suppression, inflammation, and angiogenesis. The goal is to provide new insights and potential strategies for the diagnosis and treatment of lung cancer.

Contrasting cytotoxic and regulatory T cell responses underlying distinct clinical outcomes to anti-PD-1 plus lenvatinib therapy in cancer

Combination of anti-PD-1 with lenvatinib showed clinical efficacy in multiple cancers, yet the underlying immunological mechanisms are unclear. Here, we compared T cells in hepatocellular carcinoma (HCC) patients before and after combination treatment using single-cell transcriptomics and T cell receptor (scTCR) clonotype analyses. We found that tumor-infiltrating GZMK+ CD8+ effector/effector memory T (Teff/Tem) cells, showing a favorable response to combination therapy, comprise progenitor exhausted T (Tpex) cells and also unappreciated circulating Tem (cTem) cells enriched with hepatitis B virus (HBV) specificity. Further integrated analyses revealed that cTem cells are specifically associated with responsiveness to the combination therapy, whereas Tpex cells contribute to responses in both combination therapy and anti-PD-1 monotherapy. Notably, an underexplored KIR+ CD8+ T cell subset in the tumor and FOXP3+ CD4+ regulatory T cells are specifically enriched in non-responders after the combination therapy. Our study thus elucidated T cell subsets associated with clinical benefits and resistance in cancer immunotherapy.

Advancing Immunotherapy in Pancreatic Cancer: A Brief Review of Emerging Adoptive Cell Therapies

Pancreatic cancer has the lowest 5-year survival rate (13%) among major cancers and is the third leading cause of cancer-related deaths in the United States. The high lethality of this cancer is attributed to its insidious onset, late-stage diagnosis, rapid progression, and limited treatment options. Addressing these challenges requires a deeper understanding of the complex tumor microenvironment to identify novel therapeutic targets. Newer approaches like adoptive cell therapy have shown remarkable success in treating hematological malignancies, but their application in solid tumors, particularly pancreatic cancer, is still in the early stages of development. ACT broadly involves isolating immune cells (T lymphocytes, Natural Killer cells, and macrophages) from the patient, followed by genetic engineering to enhance and mount a specific anti-tumor response. Various ACT modalities are under investigation for pancreatic cancer, including chimeric antigen receptor T cells (CAR-T), chimeric antigen receptor NK cells (CAR-NK), tumor-infiltrating lymphocytes (TIL), T-cell receptor (TCR)-engineered T cells, and cytokine-induced killer cells (CIK). Major hurdles have been identifying actionable tumor antigens and delivering focused cellular therapies to overcome the immunosuppressive and dense fibrotic stroma surrounding the pancreatic cancer. Further studies are needed to explore the limitations faced by cellular therapy in pancreatic cancer and identify novel combination treatment approaches in order to improve clinical outcomes.

Deciphering mechanical cues in the microenvironment: from non-malignant settings to tumor progression

The tumor microenvironment functions as a dynamic and intricate ecosystem, comprising a diverse array of cellular and non-cellular components that precisely orchestrate pivotal tumor behaviors, including invasion, metastasis, and drug resistance. While unraveling the intricate interplay between the tumor microenvironment and tumor behaviors represents a tremendous challenge, recent research illuminates a crucial biological phenomenon known as cellular mechanotransduction. Within the microenvironment, mechanical cues like tensile stress, shear stress, and stiffness play a pivotal role by activating mechanosensitive effectors such as PIEZO proteins, integrins, and Yes-associated protein. This activation initiates cascades of intrinsic signaling pathways, effectively linking the physical properties of tissues to their physiological and pathophysiological processes like morphogenesis, regeneration, and immunity. This mechanistic insight offers a novel perspective on how the mechanical cues within the tumor microenvironment impact tumor behaviors. While the intricacies of the mechanical tumor microenvironment are yet to be fully elucidated, it exhibits distinct physical attributes from non-malignant tissues, including elevated solid stresses, interstitial hypertension, augmented matrix stiffness, and enhanced viscoelasticity. These traits exert notable influences on tumor progression and treatment responses, enriching our comprehension of the multifaceted nature of the microenvironment. Through this innovative review, we aim to provide a new lens to decipher the mechanical attributes within the tumor microenvironment from non-malignant contexts, broadening our knowledge on how these factors promote or inhibit tumor behaviors, and thus offering valuable insights to identify potential targets for anti-tumor strategies.

An activin receptor-like kinase 1-governed monocytic lineage shapes an immunosuppressive landscape in breast cancer metastases

The biology centered around the TGF-β type I receptor activin receptor-like kinase (ALK) 1 (encoded by ACVRL1) has been almost exclusively based on its reported endothelial expression pattern since its first functional characterization more than 2 decades ago. Here, in efforts to better define the therapeutic context in which to use ALK1 inhibitors, we uncover a population of tumor-associated macrophages (TAMs) that, by virtue of their unanticipated Acvrl1 expression, are effector targets for adjuvant antiangiogenic immunotherapy in mouse models of metastatic breast cancer. The combinatorial benefit depended on ALK1-mediated modulation of the differentiation potential of bone marrow-derived granulocyte-macrophage progenitors, the release of CD14+ monocytes into circulation, and their eventual extravasation. Notably, ACVRL1+ TAMs coincided with an immunosuppressive phenotype and were overrepresented in human cancers progressing on therapy. Accordingly, breast cancer patients with a prominent ACVRL1hi TAM signature exhibited a significantly shorter survival. In conclusion, we shed light on an unexpected multimodal regulation of tumorigenic phenotypes by ALK1 and demonstrate its utility as a target for antiangiogenic immunotherapy.

Harnessing the tumor microenvironment: targeted cancer therapies through modulation of epithelial-mesenchymal transition

The tumor microenvironment (TME) is integral to cancer progression, impacting metastasis and treatment response. It consists of diverse cell types, extracellular matrix components, and signaling molecules that interact to promote tumor growth and therapeutic resistance. Elucidating the intricate interactions between cancer cells and the TME is crucial in understanding cancer progression and therapeutic challenges. A critical process induced by TME signaling is the epithelial-mesenchymal transition (EMT), wherein epithelial cells acquire mesenchymal traits, which enhance their motility and invasiveness and promote metastasis and cancer progression. By targeting various components of the TME, novel investigational strategies aim to disrupt the TME's contribution to the EMT, thereby improving treatment efficacy, addressing therapeutic resistance, and offering a nuanced approach to cancer therapy. This review scrutinizes the key players in the TME and the TME's contribution to the EMT, emphasizing avenues to therapeutically disrupt the interactions between the various TME components. Moreover, the article discusses the TME's implications for resistance mechanisms and highlights the current therapeutic strategies toward TME modulation along with potential caveats.

First-line combination therapy of immunotherapy plus anti-angiogenic drug for thoracic SMARCA4-deficient undifferentiated tumors in AIDS: a case report and review of the literature

Background

Thoracic SMARCA4-deficient undifferentiated tumors (SMARCA4-UT) exhibit a notably aggressive phenotype, which is associated with poor patient survival outcomes. These tumors are generally resistant to conventional cytotoxic chemotherapy, thereby limiting the availability of effective treatment options.

Case presentation

We describe a 69-year-old AIDS patient who initially presented with a fused, enlarged lymph node on the right clavicle and mild, unexplained pain under the right axilla that worsened with severe coughing episodes. An initial chest CT scan revealed multiple nodular and mass shadows in the mediastinum and multiple nodules in both lungs, as well as a small amount of pericardial effusion. Additionally, serum biomarkers of lung cancer were abnormal as follows: carcinoembryonic antigen (CEA) at 13.74 ng/mL, cytokeratin 19 fragment (CYFRA21-1) at 6.82 ng/mL, neuron-specific enolase (NSE) at 25.49 ng/mL, and progastrin-releasing peptide precursor (ProGRP) at 89.35 pg/mL. Subsequent pathology confirmed SMARCA4-deficient undifferentiated tumors. Considering that the weak immune status and intermediate PD-L1 level, the patient was treated with a first-line combination therapy of immunotherapy and anti-angiogenic drug instead of chemo-immunotherapy. The patient responded well to immunotherapy combining anti-angiogenic drugs and achieved an overall survival for more than 22 months.

Conclusion

Our study presented a rare case of thoracic SMARCA4-deficient undifferentiated tumors and AIDS, suggesting that first-line immunotherapy plus anti-angiogenic drugs as a potential therapeutic option for SMARCA4-UT patients under specific conditions.

Convergent inducers and effectors of T cell paralysis in the tumour microenvironment

Tumorigenesis embodies the formation of a heterotypic tumour microenvironment (TME) that, among its many functions, enables the evasion of T cell-mediated immune responses. Remarkably, most TME cell types, including cancer cells, fibroblasts, myeloid cells, vascular endothelial cells and pericytes, can be stimulated to deploy immunoregulatory programmes. These programmes involve regulatory inducers (signals-in) and functional effectors (signals-out) that impair CD8+ and CD4+ T cell activity through cytokines, growth factors, immune checkpoints and metabolites. Some signals target specific cell types, whereas others, such as transforming growth factor-β (TGFβ) and prostaglandin E2 (PGE2), exert broad, pleiotropic effects; as signals-in, they trigger immunosuppressive programmes in most TME cell types, and as signals-out, they directly inhibit T cells and also modulate other cells to reinforce immunosuppression. This functional diversity and redundancy pose a challenge for therapeutic targeting of the immune-evasive TME. Fundamentally, the commonality of regulatory programmes aimed at abrogating T cell activity, along with paracrine signalling between cells of the TME, suggests that many normal cell types are hard-wired with latent functions that can be triggered to prevent inappropriate immune attack. This intrinsic capability is evidently co-opted throughout the TME, enabling tumours to evade immune destruction.

Macrophage Polarisation in the Tumour Microenvironment: Recent Research Advances and Therapeutic Potential of Different Macrophage Reprogramming

BACKGROUND

Macrophages are a critical component of the innate immune system, derived from monocytes, with significant roles in anti-inflammatory and anti-tumour activities. In the tumour microenvironment, however, macrophages are often reprogrammed into tumour-associated macrophages (TAMs), which promote tumour growth, metastasis, and therapeutic resistance.

PURPOSE

To review recent advancements in the understanding of macrophage polarisation and reprogramming, highlighting their role in tumour progression and potential as therapeutic targets.

RESEARCH DESIGN

This is a review article synthesising findings from recent studies on macrophage polarisation and reprogramming in tumour biology.

STUDY SAMPLE

Not applicable (review of existing literature).

DATA COLLECTION AND/OR ANALYSIS

Key studies were identified and summarised to explore mechanisms of macrophage polarisation and reprogramming, focusing on M1/M2 polarisation, metabolic and epigenetic changes, and pathway regulation.

RESULTS

Macrophage reprogramming in the tumour microenvironment involves complex mechanisms, including phenotypic and functional alterations. These processes are influenced by M1/M2 polarisation, metabolic and epigenetic reprogramming, and various signalling pathways. TAMs play a pivotal role in tumour progression, metastasis, and therapy resistance, making them prime targets for combination therapies.

CONCLUSIONS

Understanding the mechanisms underlying macrophage polarisation and reprogramming offers promising avenues for developing therapies to counteract tumour progression. Future research should focus on translating these insights into clinical applications for effective cancer treatment.

Real‑world evaluation of the efficacy of immune checkpoint inhibitors in the treatment of metastatic breast cancer

The present study aimed to assess the efficacy and safety of immune checkpoint inhibitor (ICI)-based therapy in patients with metastatic breast cancer (MBC). Therefore, eligible patients with histologically confirmed MBC, treated with ICI-based therapy, were enrolled. The primary endpoint was progression-free survival (PFS) and the secondary endpoints included objective response rate (ORR), disease control rate (DCR), overall survival (OS) and safety. A total of 90 patients with MBC, treated with ICI-based therapy, with different treatment lines, were included in the present study. The median age was 50 years (range, 27-76). The predominant tumor subtypes were triple negative (53.3%) and luminal (31.1%) breast cancer. The majority of patients (61.1%) were heavily pretreated (lines of treatment, ≥3). Approximately half of the patients (46.7%) had ≥3 metastatic sites. The overall ORR was 36.7% (33/90 patients), while a DCR of 78.9% (71/90 patients) was also recorded. With a median follow-up of 16.0 months, the median PFS and OS were 4.9 months [95% confidence interval (CI), 3.8-6.1] and 13.9 months (95% CI, 9.5-18.2), respectively. Patients treated with ICIs as first-line therapy exhibited notable improvement, with a median PFS of 11.0 months (95% CI, 6.0-16.0) and a median OS of 24.3 months (95% CI, 11.4-37.2). In addition, the pretreatment blood platelet-to-lymphocyte ratio was an independent risk factor for PFS [hazard ratio (HR)=2.406; 95% CI, 1.325-4.370; P=0.004] and OS (HR=2.376; 95% CI, 1.059-5.328; P=0.036). The most common adverse events were nausea (44.4%), neutropenia (42.0%) and alanine aminotransferase/aspartate aminotransferase elevation (22.2%). Furthermore, three (3.3%) patients developed grade 1/2 immuno-related toxicity and recovered after supportive care. Overall, the present study suggested that the ICI-based therapy exhibited encouraging clinical outcomes with manageable toxicity in patients with MBC in real-world settings, with the most favorable efficacy in first-line treatment.

Si-Wu-Tang improves liver fibrosis by restoring liver sinusoidal endothelial cell functionality and reducing communication with hepatic stellate cells

BACKGROUND

Liver fibrosis is a complex reparative process in response to chronic liver injuries, with limited effective therapeutic options available in clinical practice. During liver fibrosis, liver sinusoidal endothelial cells (LSECs) undergo phenotypic changes and also play a role in modulating cellular communications. Si-Wu-Tang (SWT), a traditional Chinese herbal remedy, has been extensively studied for its effectiveness in treating hematological, gynecological and hepatic diseases.

MATERIALS AND METHODS

The component of SWT were identified by ultra-high-performance liquid chromatography (UHPLC). After establishing bile duct ligation (BDL)-induced liver fibrosis mice model and VEGFA-stimulated LSEC model, we invested the mechanism of SWT through RNA sequencing combined with molecular biology techniques.

RESULTS

SWT significantly improved the sinusoidal permeability and liver fibrosis induced by BDL and effectively regulated pathological processes in LSECs, such as angiogenesis, cell adhesion, basement membrane formation and defenestration. The anti-fibrosis effects of SWT were attributed to the inhibition on LSEC adhesion via COL8A1, on LSEC angiogenesis via IL-1β and the induction of LSEC defenestration by OLR1. Additionally, SWT disrupted the intercellular crosstalk between LSECs and hepatic stellate cells (HSCs) driven by IL-1β, thus alleviating liver fibrosis.

CONCLUSION

SWT collectively ameliorated liver fibrosis by inhibiting the COL8A1/IL-1β/OLR1 pathways associated with LSEC angiogenesis, adhesion and defenestration, as well as suppressing LSEC secretion of IL-1β to reduce HSC activation.

A landscape of checkpoint blockade resistance in cancer: underlying mechanisms and current strategies to overcome resistance

The discovery of immune checkpoints and the development of immune checkpoint inhibitors (ICI) have achieved a durable response in advanced-stage cancer patients. However, there is still a high proportion of patients who do not benefit from ICI therapy due to a lack of response when first treated (primary resistance) or detection of disease progression months after objective response is observed (acquired resistance). Here, we review the current FDA-approved ICI for the treatment of certain solid malignancies, evaluate the contrasting responses to checkpoint blockade in different cancer types, explore the known mechanisms associated with checkpoint blockade resistance (CBR), and assess current strategies in the field that seek to overcome these mechanisms. In order to improve current therapies and develop new ones, the immunotherapy field still has an unmet need in identifying other molecules that act as immune checkpoints, and uncovering other mechanisms that promote CBR.

Targeting Cancer: Microenvironment and Immunotherapy Innovations

In 2024, the United States was projected to experience 2 million new cancer diagnoses and approximately 611,720 cancer-related deaths, reflecting a broader global trend in which cancer cases are anticipated to exceed 35 million by 2050. This increasing burden highlights ongoing challenges in cancer treatment despite significant advances that have reduced cancer mortality by 31% since 1991. Key obstacles include the disease's inherent heterogeneity and complexity, such as treatment resistance, cancer stem cells, and the multifaceted tumor microenvironment (TME). The TME-comprising various tumor and immune cells, blood vessels, and biochemical factors-plays a crucial role in tumor growth and resistance to therapies. Recent innovations in cancer treatment, particularly in the field of immuno-oncology, have leveraged insights into TME interactions. An emerging example is the FDA-approved therapy using tumor-infiltrating lymphocytes (TILs), demonstrating the potential of cell-based approaches in solid tumors. However, TIL therapy is just one of many strategies being explored. This review provides a comprehensive overview of the emerging field of immuno-oncology, focusing on how novel therapies targeting or harnessing components of the TME could enhance treatment efficacy and address persistent challenges in cancer care.

Evaluation of Anti-Angiogenic Therapy Combined with Immunotherapy and Chemotherapy as a Strategy to Treat Locally Advanced and Metastatic Non-Small-Cell Lung Cancer

Immunotherapy has made recent improvements in disease-free survival (DFS) and/or overall survival (OS) in all stages of non-small-cell lung cancer (NSCLC). Here, we review the tumor microenvironment and its immunosuppressive effects and discuss how anti-angiogenic therapies may potentiate the anti-carcinogenic effects of immunotherapy. We also review all the past literature and discuss strategies of combining anti-angiogenic therapy and immunotherapy +/- chemotherapy and hypothesize how we can use this strategy for non-small-cell lung cancer in metastatic previously untreated/previously treated settings in previously treated EGFR-mutated NSCLC for the upfront treatment of brain metastases prior to radiation therapy and for the incorporation of this strategy into stage III unresectable disease. We assert the use of anti-angiogenic therapy and immunotherapy when combined appropriately with chemotherapy and radiotherapy has the potential to increase the long-term survivals in both the stage III and metastatic setting so that we can now consider more patients to experience curative treatment.

IFNγ-dependent metabolic reprogramming restrains an immature, pro-metastatic lymphatic state in melanoma

Lymphatic vessels play a crucial role in activating anti-tumor immune surveillance but also contribute to metastasis and systemic tumor progression. Whether distinct lymphatic phenotypes exist that govern the switch between immunity and metastasis remains unclear. Here we reveal that cytotoxic immunity normalizes lymphatic function and uncouples immune and metastatic potential. We find that in mice and humans, intratumoral lymphatic vessel density negatively correlates with productive cytotoxic immune responses and identify IFNγ as an intrinsic inhibitor of lymphangiogenesis. Specific deletion of the Ifngr1 in lymphatic endothelial cells (LECs) greatly expanded the intratumoral lymphatic network and drove the emergence of a tip-like endothelial state, promoting lymph node metastasis but not dendritic cell migration. IFNγ inhibits oxidative phosphorylation, which is required for proliferation and acquisition of the pathologic transcriptional state. Our data indicate that IFNγ induces a phenotypic switch in tumor-associated lymphatic vessels to reinforce canonical immune surveillance and block metastasis.

Leveraging the synergy between anti-angiogenic therapy and immune checkpoint inhibitors to treat digestive system cancers

The response rates to immunotherapy vary widely depending on the type of cancer and the specific treatment used and can be disappointingly low for many solid tumors. Fortunately, due to their complementary mechanisms of action, immunotherapy and anti-angiogenic therapy have synergistic effects in cancer treatment. By normalizing the tumor vasculature, anti-angiogenic therapy can improve blood flow and oxygenation to facilitate better immune cell infiltration into the tumor and enhance the effectiveness of immunotherapy. It also reduces immunosuppressive factors and enhances immune activation, to create a more favorable environment for immune cells to attack the tumor. Their combination leverages the strengths of both therapies to enhance anti-tumor effects and improve patient outcomes. This review discusses the vasculature-immunity crosstalk in the tumor microenvironment and summarizes the latest advances in combining anti-angiogenic therapy and immune checkpoint inhibitors to treat digestive system tumors.

Macrotrabecular-Massive Hepatocellular Carcinoma: A Case Report

Macrotrabecular-massive hepatocellular carcinoma (MTM-HCC) is a rare and aggressive molecular subtype of hepatocellular carcinoma (HCC) associated with a poor prognosis. Unlike typical HCC, which commonly arises in the context of cirrhosis, MTM-HCC can develop in non-cirrhotic livers, presenting unique diagnostic and therapeutic challenges. This case report describes a 35-year-old male who presented with persistent epigastric pain, fatigue, and loss of appetite. Clinical examination revealed hepatomegaly, prompting advanced imaging and laboratory investigations. Imaging studies identified a large hepatic mass with portal vein thrombosis and metastatic lesions, while histopathological analysis confirmed the diagnosis of MTM-HCC. The patient initiated treatment with a combination of immune checkpoint inhibitors and anti-angiogenic agents, which represent the current standard for advanced HCC. Despite initial adherence, disease progression was observed after four cycles of therapy. The patient passed away less than two months after his last consultation. This clinical course highlights the aggressive nature of MTM-HCC and its limited responsiveness to existing therapeutic protocols. MTM-HCC is characterized by distinctive histological and molecular features that differentiate it from other HCC subtypes. These include specific genetic mutations and protein expression patterns that contribute to its aggressive behavior and poor prognosis. Advanced imaging modalities combined with histopathological analysis remain crucial for accurate diagnosis and classification. This case emphasizes the critical need for heightened clinical vigilance, particularly in younger patients with atypical presentations of liver disease. It also underscores the importance of developing more effective, tailored therapeutic strategies for MTM-HCC. Further research into its molecular characteristics and inclusion in clinical trials is essential to improving outcomes for patients with this challenging and understudied subtype of liver cancer.

Immunomodulation by endothelial cells: prospects for cancer therapy

Growing evidence highlights the importance of tumor endothelial cells (TECs) in the tumor microenvironment (TME) for promoting tumor growth and evading immune responses. Immunomodulatory endothelial cells (IMECs) represent a distinct plastic phenotype of ECs that exerts the ability to modulate immunity in health and disease. This review discusses our current understanding of IMECs in cancer biology, scrutinizing insights from single-cell reports to compare their characteristics and function dynamics across diverse tumor types, conditions, and species. We investigate possible implications of exploiting IMECs in the context of cancer treatment, particularly examining their influence on the efficacy of existing therapies and the potential to leverage them as targets in optimizing immunotherapeutic strategies.

CD74+ fibroblasts proliferate upon mechanical stretching to promote angiogenesis in keloids

The healing of human skin wounds is susceptible to perturbation caused by excessive mechanical stretching, resulting in enlarged scars, hypertrophic scars, or even keloids in predisposed individuals. Keloids are fibro-proliferative scar tissues that extend beyond the initial wound boundary, consisting of the actively progressing periphery and the quiescent center. The stretch-associated outgrowth and enhanced angiogenesis are two features of the periphery of keloids. However, which cell population is responsible for transducing the mechanical stimulation to the progression of keloids remains unclear. Herein, through integrative analysis of single-cell RNA sequencing of keloids, we identified CD74+ fibroblasts, a previously unappreciated subset of fibroblasts with pro-angiogenic and stretch-induced proliferative capacities, as a key player in stretch-induced progression of keloids. Immunostaining of keloid cryosections depicted a predominant distribution of CD74+ fibroblasts in the periphery, interacting with the vasculature. In vitro tube formation assays on purified CD74+ fibroblasts ascertained their pro-angiogenic function. BrdU assays revealed that these cells proliferate upon stretching, through PIEZO1-mediated calcium influx and the downstream ERK and AKT signaling. Collectively, our findings propose a model wherein CD74+ fibroblasts serve as pivotal drivers of stretch-induced keloid progression, fueled by their proliferative and pro-angiogenic activities. Targeting the attributes of CD74+ fibroblasts holds promise as a therapeutic strategy for the management of keloids.

Perioperative sintilimab and neoadjuvant anlotinib plus chemotherapy for resectable non-small-cell lung cancer: a multicentre, open-label, single-arm, phase 2 trial (TD-NeoFOUR trial)

This open-label, single-arm, phase 2 trial evaluated the efficacy and safety of neoadjuvant sintilimab combined with anlotinib and chemotherapy, followed by adjuvant sintilimab, for resectable NSCLC. Forty-five patients received anlotinib (10 mg, QD, PO, days 1-14), sintilimab (200 mg, day 1), and platinum-based chemotherapy of each three-week cycle for 3 cycles, followed by surgery within 4-6 weeks. Adjuvant sintilimab (200 mg) was administered every 3 weeks. The primary endpoint was achieving a pathological complete response (pCR). From June 10, 2021 through October 10, 2023, 45 patients were enrolled and composed the intention-to-treat population. Twenty-six patients (57.8%) achieved pCR, and 30 (66.7%) achieved major pathological response (MPR). Forty-one patients underwent surgery. In the per-protocol set (PP set), 63.4% (26/41) achieved pCR, and 73.2% achieved MPR. The median event-free survival was not attained (95% CI, 25.1-NE). During the neoadjuvant treatment phase, grade 3 or 4 treatment-related adverse events were observed in 25 patients (55.6%), while immune-related adverse events were reported in 7 patients (15.6%). We assessed vascular normalization and infiltration of immune-related cells by detecting the expression of relevant cell markers in NSCLC tissues with mIHC. Significant tumor microenvironment changes were observed in pCR patients, including reduced VEGF+ cells and CD4+Foxp3+ Treg cells, and increased perivascular CD4+ T cells, CD39+CD8+ T cells, and M1 macrophages. In conclusion, perioperative sintilimab and neoadjuvant anlotinib plus chemotherapy achieved pCR in a notable proportion of patients with resectable NSCLC and were associated with profound changes in the tumour microenvironment (ClinicalTrials.gov NCT05400070).

Targeting the tumour vasculature: from vessel destruction to promotion

As angiogenesis was recognized as a core hallmark of cancer growth and survival, several strategies have been implemented to target the tumour vasculature. Yet to date, attempts have rarely been so diverse, ranging from vessel growth inhibition and destruction to vessel normalization, reprogramming and vessel growth promotion. Some of these strategies, combined with standard of care, have translated into improved cancer therapies, but their successes are constrained to certain cancer types. This Review provides an overview of these vascular targeting approaches and puts them into context based on our subsequent improved understanding of the tumour vasculature as an integral part of the tumour microenvironment with which it is functionally interlinked. This new knowledge has already led to dual targeting of the vascular and immune cell compartments and sets the scene for future investigations of possible alternative approaches that consider the vascular link with other tumour microenvironment components for improved cancer therapy.

The crossroad between tumor and endothelial cells

Endothelial cells are critical in tumor development, and the specific targeting of endothelial cells offers a potent means to effectively impede angiogenesis and suppress the growth of tumors. Tumor endothelial cells are responsible for the loss of anticancer immunity, the so-called endothelial anergy, i.e., the unresponsiveness of tumor endothelial cells to pro-inflammatory stimulation, not allowing adhesion of immune cells to the endothelium. Endothelial cells downregulate antigen presentation and recruitment of immune cells, contributing to immunosuppression. Targeting endothelial cells may assist in improving the immune effect of immune cells in tumor microenvironment.

Pre-metastatic niche: formation, characteristics and therapeutic implication

Distant metastasis is a primary cause of mortality and contributes to poor surgical outcomes in cancer patients. Before the development of organ-specific metastasis, the formation of a pre-metastatic niche is pivotal in promoting the spread of cancer cells. This review delves into the intricate landscape of the pre-metastatic niche, focusing on the roles of tumor-derived secreted factors, extracellular vesicles, and circulating tumor cells in shaping the metastatic niche. The discussion encompasses cellular elements such as macrophages, neutrophils, bone marrow-derived suppressive cells, and T/B cells, in addition to molecular factors like secreted substances from tumors and extracellular vesicles, within the framework of pre-metastatic niche formation. Insights into the temporal mechanisms of pre-metastatic niche formation such as epithelial-mesenchymal transition, immunosuppression, extracellular matrix remodeling, metabolic reprogramming, vascular permeability and angiogenesis are provided. Furthermore, the landscape of pre-metastatic niche in different metastatic organs like lymph nodes, lungs, liver, brain, and bones is elucidated. Therapeutic approaches targeting the cellular and molecular components of pre-metastatic niche, as well as interventions targeting signaling pathways such as the TGF-β, VEGF, and MET pathways, are highlighted. This review aims to enhance our understanding of pre-metastatic niche dynamics and provide insights for developing effective therapeutic strategies to combat tumor metastasis.

Improving tumor microenvironment assessment in chip systems through next-generation technology integration

The tumor microenvironment (TME) comprises a diverse array of cells, both cancerous and non-cancerous, including stromal cells and immune cells. Complex interactions among these cells play a central role in driving cancer progression, impacting critical aspects such as tumor initiation, growth, invasion, response to therapy, and the development of drug resistance. While targeting the TME has emerged as a promising therapeutic strategy, there is a critical need for innovative approaches that accurately replicate its complex cellular and non-cellular interactions; the goal being to develop targeted, personalized therapies that can effectively elicit anti-cancer responses in patients. Microfluidic systems present notable advantages over conventional in vitro 2D co-culture models and in vivo animal models, as they more accurately mimic crucial features of the TME and enable precise, controlled examination of the dynamic interactions among multiple human cell types at any time point. Combining these models with next-generation technologies, such as bioprinting, single cell sequencing and real-time biosensing, is a crucial next step in the advancement of microfluidic models. This review aims to emphasize the importance of this integrated approach to further our understanding of the TME by showcasing current microfluidic model systems that integrate next-generation technologies to dissect cellular intra-tumoral interactions across different tumor types. Carefully unraveling the complexity of the TME by leveraging next generation technologies will be pivotal for developing targeted therapies that can effectively enhance robust anti-tumoral responses in patients and address the limitations of current treatment modalities.

Towards Targeting Endothelial Rap1B to Overcome Vascular Immunosuppression in Cancer

The vascular endothelium, a specialized monolayer of endothelial cells (ECs), is crucial for maintaining vascular homeostasis by controlling the passage of substances and cells. In the tumor microenvironment, Vascular Endothelial Growth Factor A (VEGF-A) drives tumor angiogenesis, leading to endothelial anergy and vascular immunosuppression-a state where ECs resist cytotoxic CD8+ T cell infiltration, hindering immune surveillance. Immunotherapies have shown clinical promise. However, their effectiveness is significantly reduced by tumor EC anergy. Anti-angiogenic treatments aim to normalize tumor vessels and improve immune cell infiltration. Despite their potential, these therapies often cause significant systemic toxicities, necessitating new treatments. The small GTPase Rap1B emerges as a critical regulator of Vascular Endothelial Growth Factor Receptor 2 (VEGFR2) signaling in ECs. Our studies using EC-specific Rap1B knockout mice show that the absence of Rap1B impairs tumor growth, alters vessel morphology, and increases CD8+ T cell infiltration and activation. This indicates that Rap1B mediates VEGF-A's immunosuppressive effects, making it a promising target for overcoming vascular immunosuppression in cancer. Rap1B shares structural and functional similarities with RAS oncogenes. We propose that targeting Rap1B could enhance therapies' efficacy while minimizing adverse effects by reversing endothelial anergy. We briefly discuss strategies successfully developed for targeting RAS as a model for developing anti-Rap1 therapies.

Immune microenvironment in papillary thyroid carcinoma: roles of immune cells and checkpoints in disease progression and therapeutic implications

Papillary thyroid cancer (PTC) is the most common type of primary thyroid cancer. Despite the low malignancy and relatively good prognosis, some PTC cases are highly aggressive and even develop refractory cancer in the thyroid. Growing evidence suggested that microenvironment in tumor affected PTC biological behavior due to different immune states. Different interconnected components in the immune system influence and participate in tumor invasion, and are closely related to PTC metastasis. Immune cells and molecules are widely distributed in PTC tissues. Their quantity and proportion vary with the host's immune status, which suggests that immunotherapy may be a very promising therapeutic modality for PTC. In this paper, we review the role of immune cells and immune checkpoints in PTC immune microenvironment based on the characteristics of the PTC tumor microenvironment.

Anlotinib and anti-PD-1 mAbs perfected CIK cell therapy for lung adenocarcinoma in preclinical trials

Murine cytokine-induced killer (CIK) cells are heterologous cells that kill various allogeneic and isogenic tumors and have functional and phenotypic characteristics of natural killer cells and T lymphocytes. However, the effect of CIK cells alone on solid tumor therapy is only limited. To enhance the therapeutic effect, it is vital to discover a mix of several therapy approaches. Immune cell function is inhibited by abnormal tumor vessels and the tumor microenvironment, which block lymphocyte entry into tumor tissue. To increase the effectiveness of CIK cells' antitumor activity, antivascular therapy and CIK cell therapy can be combined. Furthermore, anlotinib is a tiny drug with multitarget tyrosine kinase inhibitors that can block cell migration, delay angiogenesis, and decrease blood vessel density. Compared with other antiangiogenesis drugs, anlotinib stands out due to the wider target of action and lower effective dose. In this work, anlotinib and murine CIK cells were coupled to boost CD3+ T cell infiltration, CD3+CD4+ T cell infiltration, and expression of granzyme B and interferon γ from CD3+CD8+ T cells, which increased the antitumor activity. Through the generation of cytotoxic cytokines by T lymphocytes, the therapeutic group using anti-PD-1 monoclonal antibodies in conjunction with anlotinib and CIK cells was more successful than the group receiving dual therapy. The preclinical study contributes to exploring the therapeutic alternatives for patients with lung adenocarcinoma, thus prolonging their lives.

ZBTB46 coordinates angiogenesis and immunity to control tumor outcome

Tumor angiogenesis and immunity show an inverse correlation in cancer progression and outcome1. Here, we report that ZBTB46, a repressive transcription factor and a widely accepted marker for classical dendritic cells (DCs)2,3, controls both tumor angiogenesis and immunity. Zbtb46 was downregulated in both DCs and endothelial cells by tumor-derived factors to facilitate robust tumor growth. Zbtb46 downregulation led to a hallmark pro-tumor microenvironment (TME), including dysfunctional vasculature and immunosuppressive conditions. Analysis of human cancer data revealed a similar association of low ZBTB46 expression with an immunosuppressive TME and a worse prognosis. In contrast, enforced Zbtb46 expression led to TME changes to restrict tumor growth. Mechanistically, Zbtb46-deficient endothelial cells were highly angiogenic, and Zbtb46-deficient bone marrow progenitors upregulated Cebpb and diverted the DC program to immunosuppressive myeloid lineage output, potentially explaining the myeloid lineage skewing phenomenon in cancer4. Conversely, enforced Zbtb46 expression normalized tumor vessels and, by suppressing Cebpb, skewed bone marrow precursors toward immunostimulatory myeloid lineage output, leading to an immune-hot TME. Remarkably, Zbtb46 mRNA treatment synergized with anti-PD1 immunotherapy to improve tumor management in preclinical models. These findings identify ZBTB46 as a critical factor for angiogenesis and for myeloid lineage skewing in cancer and suggest that maintaining its expression could have therapeutic benefits.

Mechanisms of resistance to tyrosine kinase inhibitor-targeted therapy and overcoming strategies

Tyrosine kinase inhibitor (TKI)-targeted therapy has revolutionized cancer treatment by selectively blocking specific signaling pathways crucial for tumor growth, offering improved outcomes with fewer side effects compared with conventional chemotherapy. However, despite their initial effectiveness, resistance to TKIs remains a significant challenge in clinical practice. Understanding the mechanisms underlying TKI resistance is paramount for improving patient outcomes and developing more effective treatment strategies. In this review, we explored various mechanisms contributing to TKI resistance, including on-target mechanisms and off-target mechanisms, as well as changes in the tumor histology and tumor microenvironment (intrinsic mechanisms). Additionally, we summarized current therapeutic approaches aiming at circumventing TKI resistance, including the development of next-generation TKIs and combination therapies. We also discussed emerging strategies such as the use of dual-targeted antibodies and PROteolysis Targeting Chimeras. Furthermore, we explored future directions in TKI-targeted therapy, including the methods for detecting and monitoring drug resistance during treatment, identification of novel targets, exploration of dual-acting kinase inhibitors, application of nanotechnologies in targeted therapy, and so on. Overall, this review provides a comprehensive overview of the challenges and opportunities in TKI-targeted therapy, aiming to advance our understanding of resistance mechanisms and guide the development of more effective therapeutic approaches in cancer treatment.

Immune checkpoint inhibitors targeting PD-1/PD-L1 in the treatment of human lymphomas

Non-Hodgkin lymphomas (NHLs) encompass a diverse group of malignancies arising from B cells, T cells, and natural killer (NK) cells at various stages of differentiation. Conversely, classical Hodgkin lymphomas (cHLs) primarily feature Reed-Sternberg cells (RSCs) amid a background of reactive immune cells. Immunomodulatory pathways, notably the PD-1/PD-L1 axis, play pivotal roles in tumor immune evasion across both NHLs and cHLs. Elevated expression of PD-1 and PD-L1 is observed in a spectrum of lymphomas, influencing prognosis and treatment response. Therapeutically, immune checkpoint inhibitors (ICIs) targeting PD-1/PD-L1 have revolutionized lymphoma management, particularly in relapsed/refractory cases. Nivolumab and pembrolizumab, among others, have demonstrated efficacy in various B-cell lymphomas, with promising outcomes in cHL. Combination strategies incorporating ICIs with conventional chemotherapy or targeted agents show enhanced efficacy and are being explored extensively. In this review we discuss the most important features of the tumor microenvironment of NHLs and cHLs, address the therapeutic approaches with ICIs and try to outline future perspectives.

Transmural Flow Upregulates PD-L1 Expression in Microvascular Networks

Endothelial programmed death-ligand 1 (PD-L1) expression is higher in tumors than in normal tissues. Also, tumoral vasculatures tend to be leakier than normal vessels leading to a higher trans-endothelial or transmural fluid flow. However, it is not clear whether such elevated transmural flow can control endothelial PD-L1 expression. Here, a new microfluidic device is developed to investigate the relationship between transmural flow and PD-L1 expression in microvascular networks (MVNs). After treating the MVNs with transmural flow for 24 h, the expression of PD-L1 in endothelial cells is upregulated. Additionally, CD8 T cell activation by phytohemagglutinin (PHA) is suppressed when cultured in the MVNs pre-conditioned with transmural flow. Moreover, transmural flow is able to further increase PD-L1 expression in the vessels formed in the tumor microenvironment. Finally, by utilizing blocking antibodies and knock-out assays, it is found that transmural flow-driven PD-L1 upregulation is controlled by integrin αVβ3. Overall, this study provides a new biophysical explanation for high PD-L1 expression in tumoral vasculatures.

Thetumor microenvironment'sinpancreatic cancer:Effects onimmunotherapy successandnovel strategiestoovercomethehostile environment

Cancer is a significant global health issue that poses a considerable burden on both patients and healthcare systems. Many different types of cancers exist that often require unique treatment approaches and therapies. A hallmark of tumor progression is the creation of an immunosuppressive environment, which poses complex challenges for current treatments. Amongst the most explored characteristics is a hypoxic environment, high interstitial pressure, and immunosuppressive cells and cytokines. Traditional cancer treatments involve radiotherapy, chemotherapy, and surgical procedures. The advent of immunotherapies was regarded as a promising approach with hopes of greatly increasing patients' survival and outcome. Although some success is seen with various immunotherapies, the vast majority of monotherapies are unsuccessful. This review examines how various aspects of the tumor microenvironment (TME) present challenges that impede the success of immunotherapies. Subsequently, we review strategies to manipulate the TME to facilitate the success of immunotherapies.

Incorporation of immunotherapies and nanomedicine to better normalize angiogenesis-based cancer treatment

Neoadjuvant targeting of tumor angiogenesis has been developed and approved for the treatment of malignant tumors. However, vascular disruption leads to tumor hypoxia, which exacerbates the treatment process and causes drug resistance. In addition, successful delivery of therapeutic agents and efficacy of radiotherapy require normal vascular networks and sufficient oxygen, which complete tumor vasculopathy hinders their efficacy. In view of this controversy, an optimal dose of FDA-approved anti-angiogenic agents and combination with other therapies, such as immunotherapy and the use of nanocarrier-mediated targeted therapy, could improve therapeutic regimens, reduce the need for administration of high doses of chemotherapeutic agents and subsequently reduce side effects. Here, we review the mechanism of anti-angiogenic agents, highlight the challenges of existing therapies, and present how the combination of immunotherapies and nanomedicine could improve angiogenesis-based tumor treatment.

Exploring potential predictive biomarkers through historical perspectives on the evolution of systemic therapies into the emergence of neoadjuvant therapy for the treatment of hepatocellular carcinoma

Hepatocellular carcinoma (HCC), a type of liver cancer, ranks as the sixth most prevalent cancer globally and represents the third leading cause of cancer-related deaths. Approximately half of HCC patients miss the opportunity for curative treatment and are then limited to undergoing systemic therapies. Currently, systemic therapy has entered the era of immunotherapy, particularly with the advent of immune-checkpoint inhibitors (ICIs), which have significantly enhanced outcomes for patients with advanced HCC. Neoadjuvant treatment for HCC has become a possibility-findings from the IMbrave 050 trial indicated that ICIs offer the benefit of recurrence-free survival for high-risk HCC patients post-resection or local ablation. However, only a small fraction of individuals benefit from systemic therapy. Consequently, there is an urgent need to identify predictive biomarkers for treatment response and outcome assessment. This study reviewed the historical progression of systemic therapy for HCC, highlighting notable therapeutic advancements. This study examined the development of systemic therapies involving conventional drugs and clinical trials utilized in HCC treatment, as well as potential predictive biomarkers for advanced and/or locally advanced HCC. Various studies have revealed potential biomarkers in the context of HCC treatment. These include the association of dendritic cells (DCs) with a favorable response to neoadjuvant therapy, the presence of enriched T effector cells and tertiary lymphoid structures, the identification of CD138+ plasma cells, and distinct spatial arrangements of B cells in close proximity to T cells among responders with locally advanced HCC receiving neoadjuvant cabozantinib and nivolumab treatment. Furthermore, pathological response has been associated with intratumoral cellular triads consisting of progenitor CD8+ T cells and CXCL13+ CD4+ T helper cells surrounding mature DCs in patients receiving neoadjuvant cemiplimab for resectable HCC. Despite no widely recognized predictive biomarkers for HCC individualized treatment, we believe neoadjuvant trials hold the most promise in identifying and validating them. This is because they can collect multiple samples from resectable HCC patients across stages, especially with multi-omics, bridging preclinical and clinical gaps.

Mechanisms, combination therapy, and biomarkers in cancer immunotherapy resistance

Anti-programmed death 1/programmed death ligand 1 (anti-PD-1/PD-L1) antibodies exert significant antitumor effects by overcoming tumor cell immune evasion and reversing T-cell exhaustion. However, the emergence of drug resistance causes most patients to respond poorly to these immune checkpoint inhibitors (ICIs). Studies have shown that insufficient T-cell infiltration, lack of PD-1 expression, deficient interferon signaling, loss of tumor antigen presentation, and abnormal lipid metabolism are all considered to be closely associated with immunotherapy resistance. To address drug resistance in tumor immunotherapy, a lot of research has concentrated on developing combination therapy strategies. Currently, ICIs such as anti-PD-1 /PD-L1 antibody combined with chemotherapy and targeted therapy have been approved for clinical treatment. In this review, we analyze the mechanisms of resistance to anti-PD-1/PD-L1 therapy in terms of the tumor microenvironment, gut microbiota, epigenetic regulation, and co-inhibitory immune checkpoint receptors. We also discuss various promising combination therapeutic strategies to address resistance to anti-PD-1/PD-L1 drugs, including combining these therapies with traditional Chinese medicine, non-coding RNAs, targeted therapy, other ICIs, and personalized cancer vaccines. Moreover, we focus on biomarkers that predict resistance to anti-PD-1/PD-L1 therapy as well as combination therapy efficacy. Finally, we suggest ways to further expand the application of immunotherapy through personalized combination strategies using biomarker systems.

Bioinformatics Analysis and Experimental Verification Define Different Angiogenesis Subtypes in Endometrial Carcinoma and Identify a Prognostic Signature

Increasing evidence indicates that peripheral blood vessels play a pivotal role in regulating tumor growth with the presence of new blood vessels facilitating tumor growth and metastasis. Nevertheless, the impact of specific molecule-mediated angiogenesis on the tumor immune microenvironment (TIME) and individual prognosis of uterine corpus endometrial carcinoma (UCEC) remains uncertain. The transcriptome information on 217 prognostic angiogenesis-related genes was integrated, and the angiogenesis patterns of 506 UCEC patients in The Cancer Genome Atlas (TCGA) cohort were comprehensively evaluated. We identified five angiogenic subtypes, namely, EC1, EC2, EC3, EC4, and EC5, which differed significantly in terms of prognosis, clinicopathological features, cancer hallmarks, genomic mutations, TIME patterns, and immunotherapy responses. Additionally, an angiogenesis-related prognostic risk score (APRS) was constructed to enable an individualized comprehensive evaluation. In multiple cohorts, APRS demonstrated a powerful predictive ability for the prognosis of UCEC patients. Likewise, APRS was confirmed to be associated with clinicopathological features, genomic mutations, cancer hallmarks, and TIME patterns in UCEC patients. The predictability of APRS for immune checkpoint inhibitor (ICI) therapy was also salient. Subsequently, the expression levels of four angiogenesis-related hub genes were verified by qRT-PCR, immunohistochemistry, and single-cell sequencing data analysis. The effects of four representative genes on angiogenesis were validated by Wound-Healing and Transwell assays, tube formation assay in vitro, and tumor xenograft model in vivo. This study proffered a new classification of UCEC patients based on angiogenesis. The established APRS may contribute to individualized prognosis prediction and immunotherapy selections that are better suited for UCEC patients.

Antiangiogenic-immune-checkpoint inhibitor combinations: lessons from phase III clinical trials

Antiangiogenic agents, generally antibodies or tyrosine-kinase inhibitors that target the VEGF-VEGFR pathway, are currently among the few combination partners clinically proven to improve the efficacy of immune-checkpoint inhibitors (ICIs). This benefit has been demonstrated in pivotal phase III trials across different cancer types, some with practice-changing results; however, numerous phase III trials have also had negative results. The rationale for using antiangiogenic drugs as partners for ICIs relies primarily on blocking the multiple immunosuppressive effects of VEGF and inducing several different vascular-modulating effects that can stimulate immunity, such as vascular normalization leading to increased intratumoural blood perfusion and flow, and inhibition of pro-apoptotic effects of endothelial cells on T cells, among others. Conversely, VEGF blockade can also cause changes that suppress antitumour immunity, such as increased tumour hypoxia, and reduced intratumoural ingress of co-administered ICIs. As a result, the net clinical benefits from antiangiogenic-ICI combinations will be determined by the balance between the opposing effects of VEGF signalling and its inhibition on the antitumour immune response. In this Perspective, we summarize the results from the currently completed phase III trials evaluating antiangiogenic agent-ICI combinations. We also discuss strategies to improve the efficacy of these combinations, focusing on aspects that include the deleterious functions of VEGF-VEGFR inhibition on antitumour immunity, vessel co-option as a driver of non-angiogenic tumour growth, clinical trial design, or the rationale for drug selection, dosing and scheduling.