Neutrophils and their products are increasingly recognized to have a key influence on cancer progression and response to therapy. Their involvement has been shown in nearly every aspect of cancer pathophysiology with growing evidence now supporting their role in resistance to a variety of cancer therapies. Recently, the role of neutrophils in cancer progression and therapy resistance has been further complicated with the discovery of neutrophil extracellular traps (NETs). NETs are web-like structures of chromatin decorated with a variety of microbicidal proteins. They are released by neutrophils in a process called NETosis. NET-dependent mechanisms of cancer pathology are beginning to be appreciated, particularly with respect to tumor response to chemo-, immuno-, and radiation therapy. Several studies support the functional role of NETs in cancer therapy resistance, involving T-cell exhaustion, drug detoxification, angiogenesis, the epithelial-to-mesenchymal transition, and extracellular matrix remodeling mechanisms, among others. Given this, new and promising data suggests NETs provide a microenvironment conducive to limited therapeutic response across a variety of neoplasms. As such, this paper aims to give a comprehensive overview of evidence on NETs in cancer therapy resistance with a focus on clinical applicability.

Lymph nodes (LNs) are frequently the first sites of metastasis. Currently, the only prognostic LN assessment is determining metastatic status. However, there is evidence suggesting that LN metastasis is facilitated by the formation of a pre‐metastatic niche induced by tumour derived extracellular vehicles (EVs). Therefore, it is important to detect and modify the LN environmental changes. Earlier work has demonstrated that neutrophil extracellular traps (NETs) can sequester and promote distant metastasis. Here, we first confirmed that LN NETs are associated with reduced patient survival. Next, we demonstrated that NETs deposition precedes LN metastasis and NETs inhibition diminishes LN metastases in animal models. Furthermore, we discovered that EVs are essential to the formation of LN NETs. Finally, we showed that lymphatic endothelial cells secrete CXCL8/2 in response to EVs inducing NETs formation and the promotion of LN metastasis. Our findings reveal the role of EV‐induced NETs in LN metastasis and provide potential immunotherapeutic vulnerabilities that may occur early in the metastatic cascade.

Background: Crohn's disease (CD) is a chronic inflammatory disease in the intestinal tract. Mesenteric fat wrapping and thickening, or creeping fat (CrF), is a typical characteristic of CD and it involves lymphangiogenesis and altered lymphatic function. By releasing extracellular vesicles (EVs), adipose tissue‐derived stem cells (ADSCs) can regulate their adjacent cells. However, the regulating roles of ADSC‐EVs in CrF (CrF‐EVs) in CD, especially in modulating lymphatic function and mitigating the progression of mesenteritis and colitis, remains elusive.Methods: To evaluate the regulative roles of CrF‐EVs on lymphatic functions, in vitro assays were performed using human lymphatic endothelial cells (HLECs). Next, Interleukin 10 knock‐out (Il‐10^−/−) mice were used to assess the biological functions of CrF‐EVs in spontaneous mesenteritis and colitis. Moreover, tissue and serum from various cohorts of CD patients were used to determine the prognostic value of miR‐132‐3p.Results: CrF‐EVs significantly attenuated spontaneous mesenteritis and colitis in Il‐10^−/− mice via promoting lymphangiogenesis and lymphatic drainage. Using high‐throughput sequencing, we demonstrated that CrF‐EVs significantly increased HLEC proliferation, migration, tube formation and CCL‐21 production in a miR‐132‐3p/RASA1/ERK1/2 axis‐dependent manner. Accordingly, upregulated miR‐132‐3p was observed in patient CrF, positively correlated with lymphangiogenesis while negatively correlated with inflammatory factors (tumour necrosis factor‐α and IL‐6) level. Moreover, serum miR‐132‐3p demonstrated a positive correlation with disease activity.Conclusions: EVs derived from CrF ADSCs, containing elevated levels of miR‐132‐3p, could promote lymphatic function and restrain inflammation of CD. Our results provide a novel insight into the role of mesenteric lymphatics in CD progression and reveal a new potential therapeutic.Key points: Extracellular vesicles (EVs) of creeping fat (CrF) derived adipose stem cells effectively attenuate chronic mesenteritis and colitis in Crohn's disease (CD). The lymphatic vessels play an important role in disease development of CD and their functions are improved by CrF‐EV‐miR‐132‐3p through RASA1/ERK1/2 signaling. MiR‐132‐3p expression is upregulated in CrF and serum of CD patients, and tightly linked with inflammation and disease activity.

Lymph nodes (LNs) are frequently the first sites of metastasis. Currently, the only prognostic LN assessment is determining metastasis status. However, there is evidence suggesting that LN metastasis is facilitated by a pre-metastatic niche induced by tumour derived extracellular vehicles (EVs). Therefore, it is important to detect and modify the LN environmental changes. We have previously reported that neutrophil extracellular traps (NETs) can sequester and promote distant metastasis. Here, we first confirmed that LN NETs are associated with reduced patient survival. Next, we demonstrated that NETs deposition precedes LN metastasis and NETs inhibition abolishes LN metastases in animal mode. Furthermore, we discovered that EVs are essential to the formation of LN NETs. Lymphatic endothelial cells secrete CXCL8/2 in response to EVs inducing NETs formation and the promotion of LN metastasis. Our findings are the first to reveal the role of EV induced NETs in LN metastasis and provide potential immunotherapeutic vulnerabilities. Graphic Abstract Illustrative demonstration of the LNs premetastatic niche formation induced by EVs and NETs. Primary tumour constantly secretes EVs, which were actively uptaken by LECs. LECs subsequently secretes CXCL8 or CXCL2 upon EV reception. CXCL8 and CXCL2 are both neutrophil chemoattractants and potent NETs inducers. The following neutrophil recruitment and NETs formation lead to increased LN metastasis burden.

A major limitation in studying gastroesophageal adenocarcinoma (GEA) has been the lack of reliable models that represent the disease’s complexity. We present lessons learned from a comprehensive large-scale biobanking effort combining traditional sample collection with several in vitro models, including 3-dimensional patient-derived organoids (PDOs), 2-dimensional cancer-associated fibroblasts (CAFs), tumor-infiltrating lymphocytes (TILs), and/or in vivo xenografts. This initiative started in 2018, integrating multiple advanced ex vivo models such as PDOs, patient-derived xenografts (PDXs), and organoids (PDXOs). This unique resource now includes tumor avatars from over 380 consented patients, making it the world’s largest living GEA biobank. We achieved a >90% success rate in creating per-patient models, including 227 tumor-derived and 203 neighboring normal PDOs. These organoids accurately mirror key features of the original tumors, such as their histology (e.g., microsatellite instability), mutations, and drug response across treatment points. Notably, PDOs can predict individual patient responses to chemotherapy within five weeks, underscoring their clinical relevance. Furthermore, high-throughput drug screening on PDO subsets with known genetic landscapes generates personalized chemosensitivity profiles for 22 drugs. Through a process of continued refinement of culture techniques and tumor sampling approach, our large-scale comprehensive collection of GEA avatars represents a unique and valuable preclinical experimental resource for precision oncology.