Chemokines as Regulators of Neutrophils: Focus on Tumors, Therapeutic Targeting, and Immunotherapy

The adhesion-GPCR ADGRF5 fuels breast cancer progression by suppressing the MMP8-mediated antitumorigenic effects

ADGRF5 (GPR116) has been identified as a facilitator of breast cancer cell migration and metastasis, yet the underlying mechanisms remain largely elusive. Our current study reveals that the absence of ADGRF5 in breast cancer cells impairs extracellular matrix (ECM)-associated cell motility and impedes in vivo tumor growth. This correlates with heightened expression of matrix metalloproteinase 8 (MMP8), a well-characterized antitumorigenic MMP, and a shift in the polarization of tumor-associated neutrophils (TANs) towards the antitumor N1 phenotype in the tumor microenvironment (TME). Mechanistically, ADGRF5 inhibits ERK1/2 activity by enhancing RhoA activation, leading to decreased phosphorylation of C/EBPβ at Thr235, hindering its nuclear translocation and subsequent activation. Crucially, two C/EBPβ binding motifs essential for MMP8 transcription are identified within its promoter region. Consequently, ADGRF5 silencing fosters MMP8 expression and CXCL8 secretion, attracting increased infiltration of TANs; simultaneously, MMP8 plays a role in decorin cleavage, which leads to trapped-inactivation of TGF-β in the TME, thereby polarizing TANs towards the antitumor N1 neutrophil phenotype and mitigating TGF-β-enhanced cell motility in breast cancer. Our findings reveal a novel connection between ADGRF5, an adhesion G protein-coupled receptor, and the orchestration of the TME, which dictates malignancy progression. Overall, the data underscore ADGRF5 as a promising therapeutic target for breast cancer intervention.

Immunomodulatory Effects of Histone Variant H2A.J in Ionizing Radiation Dermatitis

PURPOSE

Histone variant H2A.J is associated with premature senescence after ionizing radiation (IR) and modulates senescence-associated secretory phenotype (SASP). Using constitutive H2A.J knock-out mice, the role of H2A.J was investigated in radiation dermatitis.

METHODS AND MATERIALS

H2A.J wild-type (WT) and knock-out (KO) mice were exposed to moderate or high IR doses (≤20 Gy, skinfold IR). Radiation-induced skin reactions were investigated up to 2 weeks post-IR at macroscopic and microscopic levels. H2A.J and other senescence markers, as well as DNA damage and proliferation markers, were studied by immunohistochemistry, immunofluorescence, and electron microscopy. After high-dose IR, protein-coding transcriptomes were analyzed by RNA sequencing, immune cell infiltration by flow cytometry, and gene expression by reverse transcription polymerase chain reaction in (non-) irradiated WT versus KO skin.

RESULTS

In WT skin, epidermal keratinocytes showed time- and dose-dependent H2A.J accumulation after IR exposure. Unexpectedly, stronger inflammatory reactions with increased epidermal thickness and progressive hair follicle loss were observed in irradiated KO versus WT skin. Clearly more radiation-induced senescence was observed in keratinocyte populations of KO skin after moderate and high doses, with hair follicle stem cells being particularly badly damaged, leading to follicle atrophy. After high-dose IR, transcriptomic analysis revealed enhanced senescence-associated signatures in irradiated KO skin, with intensified release of SASP factors. Flow cytometric analysis indicated increased immune cell infiltration in both WT and KO skin; however, specific chemokine-mediated signaling in irradiated KO skin led to more neutrophil recruitment, thereby aggravating radiation toxicities. Increased skin damage in irradiated KO skin led to hyperproliferation, abnormal differentiation, and cornification of keratinocytes, accompanied by increased upregulation of transcription-factor JunB.

CONCLUSIONS

Lack of radiation-induced H2A.J expression in keratinocytes is associated with increased senescence induction, modulation of SASP expression, and exacerbated inflammatory skin reactions. Hence, epigenetic H2A.J-mediated gene expression in response to IR regulates keratinocyte immune functions and plays an essential role in balancing the inflammatory response during radiation dermatitis.

Chitinase 3-like-1 Expression in the Microenvironment Is Associated with Neutrophil Infiltration in Bladder Cancer

Bladder cancer is a common cancer with well-established therapeutic strategies. However, recurrence occurs in 50% of patients with non-muscle-invasive bladder cancer, and 20% of patients progress to muscle-invasive bladder cancer. The 5-year survival rate for muscle-invasive bladder cancer patients is disappointingly low, ranging from 36% to 48%. A molecular marker of interest is chitinase 3-like-1 (CHI3L1), which is elevated in various cancers, including bladder cancer. In addition to its role in cancer cells, CHI3L1 also has regulatory abilities in immune cells. Neutrophil infiltration has been shown to positively correlate with overall survival, progression-free survival, and relapse-free survival in bladder cancer patients. However, the relationship between CHI3L1 and neutrophils remain poorly understood. Therefore, this study investigated the relationship between CHI3L1 level and protumor neutrophil infiltration in bladder cancer. We analyzed the GSE128959 dataset and the data of a bladder cancer cohort undergoing chemotherapy. We observed higher expression of CHI3L1 in bladder cancer patients with invasive or chemotherapy-resistance. Our results revealed a positive correlation between CHI3L1 expression and protumor neutrophil infiltration. Elevated CHI3L1 expression was associated with genes which were related to the recruitment and infiltration of neutrophils. Consequently, CHI3L1 may serve as a novel evaluation factor for the degree of neutrophil infiltration in advanced bladder cancer in those scheduled for chemotherapy.

Evolutionary traits and functional roles of chemokines and their receptors in the male pregnancy of the Syngnathidae

Vertebrates have developed various modes of reproduction, some of which are found in Teleosts. Over 300 species of the Syngnathidae (seahorses, pipefishes and seadragons) exhibit male pregnancies; the males have specialized brood pouches that provide immune protection, nourishment, and oxygen regulation. Chemokines play a vital role at the mammalian maternal-fetal interface; however, their functions in fish reproduction are unclear. This study revealed the evolutionary traits and potential functions of chemokine genes in 22 oviparous, ovoviviparous, and viviparous fish species through comparative genomic analyses. Our results showed that chemokine gene copy numbers and evolutionary rates vary among species with different modes of reproduction. Syngnathidae lost cxcl13 and cxcr5, which are involved in key receptor-ligand pairs for lymphoid organ development. Notably, Syngnathidae have site-specific mutations in cxcl12b and ccl44, suggesting immune function during gestation. Moreover, transcriptome analysis revealed that chemokine gene expression varies among Syngnathidae species with different types of brood pouches, suggesting adaptive variations in chemokine functions among seahorses and their relatives. Furthermore, challenge experiments on seahorse brood pouches revealed a joint immune function of chemokine genes during male pregnancy. This study provides insights into the evolutionary diversity of chemokine genes associated with different reproductive modes in fish.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42995-023-00205-x.

Circulating neutrophils activated by cancer cells and M2 macrophages promote gastric cancer progression during PD-1 antibody-based immunotherapy

Aims: To analyze the correlation between the neutrophil-to-lymphocyte ratio (NLR) and prognosis of advanced gastric cancer (AGC) patients treated by PD-1 antibody-based therapy and to delineate molecular characteristics of circulating neutrophils by single-cell RNA sequencing (scRNA-seq). Methods: The clinicopathological information of 45 AGC patients receiving PD-1 antibody-based regimens at the Department of Oncology, Ruijin Hospital, was reviewed. Treatment outcomes including objective response rate (ORR), progression-free survival (PFS), and overall survival (OS) were recorded. The correlation between NLR and efficacy of PD-1 antibody-based treatment was analyzed. Single-cell RNA sequencing (scRNA-seq) analysis was performed based on multisite biopsy samples from two AGC patients to explore the molecular characteristics of circulating neutrophils and their pro-tumor mechanisms. Tissue samples from 88 gastric cancer patients who underwent radial gastrectomy were collected for immunochemistry staining. Results: A high posttreatment NLR was associated with poor outcomes of AGC patients receiving PD-1 antibody-based regimens. scRNA-seq analysis showed that an increased number of circulating neutrophils were found in peripheral blood samples after treatment in which neutrophil cluster 1 (NE-1) was the major subcluster. NE-1 was featured with a neutrophil activation phenotype with the high expression of MMP9, S100A8, S100A9, PORK2, and TGF-β1. NE-1 displayed an intermediate state in pseudotime trajectory analysis with gene function enrichment found in neutrophil activation, leukocyte chemotaxis, and negative regulation of MAP kinase activity. Cellular interaction analysis showed that the chemokine signaling pathway is the major interactional pathway of NE-1 between subclusters of malignant epithelial cells (EP-4) and M2 macrophages (M2-1 and M2-2). In turn, the MAPK signaling pathway and Jak-STAT signaling pathway of EP-4, including IL1B/IL1RAP, OSM/OSMR, and TGFB1/TGFBR2 axes, were identified as interacting pathways between EP-4 and NE-1. The high expression of OSMR in tumor cells was closely correlated with lymph node metastasis of gastric cancer. Conclusion: The posttreatment NLR could be a poor prognostic marker of AGC patients treated with immune checkpoint inhibitors (ICIs). Subclusters of circulating neutrophils activated by tumor cells and M2 macrophages could participate in gastric cancer progression through signaling interactions with tumor cells.

Targeting Angiogenesis in the Era of Biliary Tract Cancer Immunotherapy: Biological Rationale, Clinical Implications, and Future Research Avenues

Although biliary tract cancers are traditionally considered rare in Western countries, their incidence and mortality rates are rising worldwide. A better knowledge of the genomic landscape of these tumor types has broadened the number of molecular targeted therapies, including angiogenesis inhibitors. The role of immune checkpoint inhibitors (ICIs) could potentially change the first-line therapeutic approach, but monotherapy with ICIs has shown disappointing results in CCA. Several clinical trials are evaluating combination strategies that include immunotherapy together with other anticancer agents with a synergistic activity. The tumor microenvironment (TME) composition plays a pivotal role in the prognosis of BTC patients. The accumulation of immunosuppressive cell types, such as tumor-associated macrophages (TAMs) and regulatory T-cells, together with the poor infiltration of cytotoxic CD8+ T-cells, is known to predispose to a poor prognosis owing to the establishment of resistance mechanisms. Likewise, angiogenesis is recognized as a major player in modulating the TME in an immunosuppressive manner. This is the mechanistic rationale for combination treatment schemes blocking both immunity and angiogenesis. In this scenario, this review aims to provide an overview of the most recent completed or ongoing clinical trials combining immunotherapy and angiogenesis inhibitors with/without a chemotherapy backbone.

Advances, challenge and prospects in cell-mediated nanodrug delivery for cancer therapy: a review

Nanomedicine offers considerable opportunities to improve drugability and reduce toxicity for tumour therapy. However, the application of nanomedicine has achieved little success in clinical trials due to multiple physiological barriers to drug delivery. Circulating cells are expected to improve the physical distribution of drugs and enhance the therapeutic effect by overcoming various biological barriers in collaboration with nano-drug delivery systems owing to excellent biocompatibility, low immunogenicity and a long-circulation time and strong binding specificity. Nonetheless, we have noticed some limitations in implementing tthe strategy. In this article, we intend to introduce the latest progress in research and application of circulating cell-mediated nano-drug delivery systems, describe the main cell-related drug delivery modes, sum up the relevant points of the transport systems in the process of loading, transport and release, and lastly discuss the advantages, challenges and future development trends in cell-mediated nano-drug delivery.

How Can We Improve Vaccination Response in Old People? Part I: Targeting Immunosenescence of Innate Immunity Cells

Vaccination, being able to prevent millions of cases of infectious diseases around the world every year, is the most effective medical intervention ever introduced. However, immunosenescence makes vaccines less effective in providing protection to older people. Although most studies explain that this is mainly due to the immunosenescence of T and B cells, the immunosenescence of innate immunity can also be a significant contributing factor. Alterations in function, number, subset, and distribution of blood neutrophils, monocytes, and natural killer and dendritic cells are detected in aging, thus potentially reducing the efficacy of vaccines in older individuals. In this paper, we focus on the immunosenescence of the innate blood immune cells. We discuss possible strategies to counteract the immunosenescence of innate immunity in order to improve the response to vaccination. In particular, we focus on advances in understanding the role and the development of new adjuvants, such as TLR agonists, considered a promising strategy to increase vaccination efficiency in older individuals.

Emerging Roles of Chemokines in Cancer Immunotherapy

This series of 15 articles (4 original articles and 11 reviews) is presented by international leaders in chemokine research [...]