c-Met Mediated Cytokine Network Promotes Brain Metastasis of Breast Cancer by Remodeling Neutrophil Activities

The tumor-neutrophil interactions in the microenvironment of brain metastases with different primary sites

Brain metastases originating from lung and breast cancer can recruit and activate neutrophils to acquire a tumor-promoting phenotype. It is currently unclear if this phenomenon also occurs in brain metastases arising from other primary sites. Here, we investigated the effect of tumor cells isolated from melanoma, lung cancer, and gastrointestinal cancer brain metastases on neutrophil biology and functions. We found that lung and gastrointestinal but not melanoma brain metastasis cells produced CXCL8/IL-8 and promoted neutrophil recruitment. Similarly, lung and gastrointestinal but not melanoma brain metastasis cells prolonged the survival of neutrophils and stimulated them to release MMP9 and CCL4/MIP1β. In situ, lung and gastrointestinal brain metastasis tissues contained significantly higher numbers of tumor-infiltrating neutrophils compared to melanoma brain metastases. The levels of neutrophil infiltration significantly correlated with the proliferation index of these tumors. Our findings identify variabilities in the immune microenvironment of brain metastases with different primary sites, which may ultimately affect their pathophysiology and progression.

Metastatic brain tumors: from development to cutting-edge treatment

Metastatic brain tumors, also called brain metastasis (BM), represent a challenging complication of advanced tumors. Tumors that commonly metastasize to the brain include lung cancer and breast cancer. In recent years, the prognosis for BM patients has improved, and significant advancements have been made in both clinical and preclinical research. This review focuses on BM originating from lung cancer and breast cancer. We briefly overview the history and epidemiology of BM, as well as the current diagnostic and treatment paradigms. Additionally, we summarize multiomics evidence on the mechanisms of tumor occurrence and development in the era of artificial intelligence and discuss the role of the tumor microenvironment. Preclinically, we introduce the establishment of BM models, detailed molecular mechanisms, and cutting-edge treatment methods. BM is primarily treated with a comprehensive approach, including local treatments such as surgery and radiotherapy. For lung cancer, targeted therapy and immunotherapy have shown efficacy, while in breast cancer, monoclonal antibodies, tyrosine kinase inhibitors, and antibody-drug conjugates are effective in BM. Multiomics approaches assist in clinical diagnosis and treatment, revealing the complex mechanisms of BM. Moreover, preclinical agents often need to cross the blood-brain barrier to achieve high intracranial concentrations, including small-molecule inhibitors, nanoparticles, and peptide drugs. Addressing BM is imperative.

The impact of rhG-CSF on risk of recurrence after postoperative chemotherapy in NSCLC Patients: A retrospective cohort study

PURPOSE

Recombinant human granulocyte colony-stimulating factor (rhG-CSF) is widespread in the prevention and treatment of blood-related toxic effects associated with chemotherapy. This study aimed to explore the correlation between rhG-CSF and the recurrence of non-small cell lung cancer (NSCLC) in patients who have undergone postoperative chemotherapy.

METHODS

Our study encompassed 517 NSCLC patients at pathological stage I-III, who underwent surgical removal and subsequent chemotherapy from January 2012 to December 2019 at the First Affiliated Hospital of Nanchang University. The research focused on evaluating the separate impact of rhG-CSF on the likelihood of postoperative recurrence. The analysis employed both univariate and multivariate Cox regression models.

RESULTS

Of 517 NSCLC patients, 123 patients did not receive rhG-CSF, while 394 patients received rhG-CSF. Unexpectedly, it was discovered that rhG-CSF usage correlated with the emergence of distant metastasis (HR: 1.8, 95 %CI 1.2-2.7, p = 0.005), though not with local recurrence (HR: 1.4, 95 %CI 0.9-2.3, p = 0.142). By multifactorial Cox analysis, rhG-CSF was an independent risk factor for distant metastasis (adjusted HR: 1.7, 95 %CI 1.0-2.6, p = 0.033). We additionally discovered that rhG-CSF could increase the risk of brain metastasis (adjusted HR: 3.9, 95 %CI 1.5-9.8, p = 0.005) and bone metastasis (adjusted HR: 3.1, 95 %CI 1.2-8.2, p = 0.02).

CONCLUSION

Our findings indicate that rhG-CSF independently contributes to the risk of distant metastasis, yet it shows no correlation with local recurrence. Furthermore, employing rhG-CSF played a crucial role in predicting brain metastasis and bone metastasis after postoperative chemotherapy in NSCLC patients.

Antibody-Drug Conjugates for the Treatment of Non-Small Cell Lung Cancer with Central Nervous System Metastases

Antibody-drug conjugates (ADCs) represent an emerging class of targeted anticancer agents that have demonstrated impressive efficacy in numerous cancer types. In non-small cell lung cancer (NSCLC), ADCs have become a component of the treatment armamentarium for a subset of patients with metastatic disease. Emerging data suggest that some ADCs exhibit impressive activity even in central nervous system (CNS) metastases, a disease site that is difficult to treat and associated with poor prognosis. Herein, we describe and summarize the existing evidence surrounding ADCs in NSCLC with a focus on CNS activity.

Neutrophils in the premetastatic niche: key functions and therapeutic directions

Metastasis has been one of the primary reasons for the high mortality rates associated with tumours in recent years, rendering the treatment of current malignancies challenging and representing a significant cause of recurrence in patients who have undergone surgical tumour resection. Halting tumour metastasis has become an essential goal for achieving favourable prognoses following cancer treatment. In recent years, increasing clarity in understanding the mechanisms underlying metastasis has been achieved. The concept of premetastatic niches has gained widespread acceptance, which posits that tumour cells establish a unique microenvironment at distant sites prior to their migration, facilitating their settlement and growth at those locations. Neutrophils serve as crucial constituents of the premetastatic niche, actively shaping its microenvironmental characteristics, which include immunosuppression, inflammation, angiogenesis and extracellular matrix remodelling. These characteristics are intimately associated with the successful engraftment and subsequent progression of tumour cells. As our understanding of the role and significance of neutrophils in the premetastatic niche deepens, leveraging the presence of neutrophils within the premetastatic niche has gradually attracted the interest of researchers as a potential therapeutic target. The focal point of this review revolves around elucidating the involvement of neutrophils in the formation and shaping of the premetastatic niche (PMN), alongside the introduction of emerging therapeutic approaches aimed at impeding cancer metastasis.

Unveiling the Role of HGF/c-Met Signaling in Non-Small Cell Lung Cancer Tumor Microenvironment

Non-small cell lung cancer (NSCLC) is characterized by several molecular alterations that contribute to its development and progression. These alterations include the epidermal growth factor receptor (EGFR), anaplastic lymphoma kinase (ALK), human epidermal growth factor receptor 2 (HER2), and mesenchymal-epithelial transition factor (c-MET). Among these, the hepatocyte growth factor (HGF)/c-MET signaling pathway plays a crucial role in NSCLC. In spite of this, the involvement of the HGF/c-MET signaling axis in remodeling the tumor microenvironment (TME) remains relatively unexplored. This review explores the biological functions of the HGF/c-MET signaling pathway in both normal and cancerous cells, examining its multifaceted roles in the NSCLC tumor microenvironment, including tumor cell proliferation, migration and invasion, angiogenesis, and immune evasion. Furthermore, we summarize the current progress and clinical applications of MET-targeted therapies in NSCLC and discuss future research directions, such as the development of novel MET inhibitors and the potential of combination immunotherapy.

Lipocalin-2 promotes breast cancer brain metastasis by enhancing tumor invasion and modulating brain microenvironment

Breast cancer is the leading cancer diagnosed in women globally, with brain metastasis emerging as a major cause of death, particularly in human epidermal growth factor receptor 2 positive and triple-negative breast cancer subtypes. Comprehensive understanding of the molecular foundations of central nervous system metastases is imperative for the evolution of efficacious treatment strategies. Lipocalin-2 (LCN2), a secreted iron transport protein with multiple functions, has been linked to the progression of breast cancer brain metastasis (BCBM). In primary tumors, LCN2 promotes the proliferation and angiogenesis of breast cancer cells, triggers the epithelial-mesenchymal transition, interacts with matrix metalloproteinase-9, thereby facilitating the reorganization of the extracellular matrix and enhancing cancer cell invasion and migration. In brain microenvironment, LCN2 undermines the blood-brain barrier and facilitates tumor seeding in the brain by modulating the behavior of key cellular components. In summary, this review meticulously examines the fuel role of LCN2 in BCBM cascade, and investigates the potential mechanisms involved. It highlights the potential of LCN2 as both a therapeutic target and biomarker, indicating that interventions targeting LCN2 may offer improved outcomes for patients afflicted with BCBM.

Neutrophils in cancer: dual roles through intercellular interactions

Neutrophils, the most abundant immune cells in human blood, play crucial and diverse roles in tumor development. In the tumor microenvironment (TME), cancer cells regulate the recruitment and behaviors of neutrophils, transforming some of them into a pro-tumor phenotype. Pro-tumor neutrophils interact with cancer cells in various ways to promote cancer initiation, growth, and metastasis, while anti-tumor neutrophils interact with cancer cells to induce senescence and death. Neutrophils can also interact with other cells in TME, including T cells, macrophages, stromal cells, etc. to exert anti- or pro-tumor functions. In this review, we will analyze the anti- and pro-tumor intercellular interactions mediated by neutrophils, with a focus on generalizing the mechanisms underlying the interaction of neutrophils with tumor cells and T cells. Furthermore, we will provide an overview of cancer treatment strategies targeting neutrophil-mediated cellular interactions.

Neutrophils as potential therapeutic targets for breast cancer

Breast cancer (BC) remains the foremost cause of cancer mortality globally, with neutrophils playing a critical role in its pathogenesis. As an essential tumor microenvironment (TME) component, neutrophils are emerging as pivotal factors in BC progression. Growing evidence has proved that neutrophils play a Janus- role in BC by polarizing into the anti-tumor (N1) or pro-tumor (N2) phenotype. Clinical trials are evaluating neutrophil-targeted therapies, including Reparixin (NCT02370238) and Tigatuzumab (NCT01307891); however, their clinical efficacy remains suboptimal. This review summarizes the evidence regarding the close relationship between neutrophils and BC, emphasizing the critical roles of neutrophils in regulating metabolic and immune pathways. Additionally, we summarize the existing therapeutic approaches that target neutrophils, highlighting the challenges, and affirming the rationale for continuing to explore neutrophils as a viable therapeutic target in BC management.