Neutrophil infiltration into human gliomas

Glioblastoma Contains Topologically Distinct Proliferative and Metabolically Defined Subpopulations of Nestin- and Glut1-Expressing Cells

The difficulty in treatment of glioblastoma is a consequence of its natural infiltrative growth and the existence of a population of therapy-resistant glioma cells that contribute to growth and recurrence. To identify cells more likely to have these properties, we examined the expression in tumor specimens of several protein markers important for glioma progression including the intermediate filament protein, Nestin (NES), a glucose transporter (Glut1/SLC2A1), the glial lineage marker, glial fibrillary acidic protein, and the proliferative indicator, Ki-67. We also examined the expression of von Willebrand factor, a marker for endothelial cells as well as the macrophage/myeloid markers CD163 and CD15. Using a multicolor immunofluorescence and hematoxylin and eosin staining approach with archival formalin-fixed, paraffin embedded tissue from primary, recurrent, and autopsy IDH1 wildtype specimens combined with high-resolution tissue image analysis, we have identified highly proliferative NES(+)/Glut1(-) cells that are preferentially perivascular. In contrast, Glut1(+)/NES(-) cells are distant from blood vessels, show low proliferation, and are preferentially located at the borders of pseudopalisading necrosis. We hypothesize that Glut1(+)/NES(-) cells would be naturally resistant to conventional chemotherapy and radiation due to their low proliferative capacity and may act as a reservoir for tumor recurrence.

S100A gene family: immune-related prognostic biomarkers and therapeutic targets for low-grade glioma

BACKGROUND

Despite the better prognosis given by surgical resection and chemotherapy in low-grade glioma (LGG), progressive transformation is still a huge concern. In this case, the S100A gene family, being capable of regulating inflammatory responses, can promote tumor development.

METHODS

The analysis was carried out via ONCOMINE, GEPIA, cBioPortal, String, GeneMANIA, WebGestalt, LinkedOmics, TIMER, CGGA, R 4.0.2 and immunohistochemistry.

RESULTS

S100A2, S100A6, S100A10, S100A11, and S100A16 were up-regulated and S100A1 and S100A13 were down-regulated in LGG compared to normal tissues. S100A3, S100A4, S100A8, and S100A9 expression was up-regulated during the progression of glioma grade. In addition, genetic variation of the S100A family was high in LGG, and the S100A family genes mostly function through IL-17 signaling pathway, S100 binding protein, and inflammatory responses. The TIMER database also revealed a relationship between gene expression and immune cell infiltration. High expression of S100A2, S100A3, S100A4, S100A6, S100A8, S100A9, S100A10, S100A11, S100A13, and S100A16 was significantly associated with poor prognosis in LGG patients. S100A family genes S100A2, S100A3, S100A6, S100A10, and S100A11 may be prognosis-related genes in LGG, and were significantly associated with IDH mutation and 1p19q codeletion. The immunohistochemical staining results also confirmed that S100A2, S100A3, S100A6, S100A10, and S100A11 expression was upregulated in LGG.

CONCLUSION

The S100A family plays a vital role in LGG pathogenesis, presumably facilitating LGG progression via modulating inflammatory state and immune cell infiltration.

Blood-Based Biomarkers for Glioma in the Context of Gliomagenesis: A Systematic Review

BACKGROUND

Gliomas are the most common and aggressive tumors of the central nervous system. A robust and widely used blood-based biomarker for glioma has not yet been identified. In recent years, a plethora of new research on blood-based biomarkers for glial tumors has been published. In this review, we question which molecules, including proteins, nucleic acids, circulating cells, and metabolomics, are most promising blood-based biomarkers for glioma diagnosis, prognosis, monitoring and other purposes, and align them to the seminal processes of cancer.

METHODS

The Pubmed and Embase databases were systematically searched. Biomarkers were categorized in the identified biomolecules and biosources. Biomarker characteristics were assessed using the area under the curve (AUC), accuracy, sensitivity and/or specificity values and the degree of statistical significance among the assessed clinical groups was reported.

RESULTS

7,919 references were identified: 3,596 in PubMed and 4,323 in Embase. Following screening of titles, abstracts and availability of full-text, 262 articles were included in the final systematic review. Panels of multiple biomarkers together consistently reached AUCs >0.8 and accuracies >80% for various purposes but especially for diagnostics. The accuracy of single biomarkers, consisting of only one measurement, was far more variable, but single microRNAs and proteins are generally more promising as compared to other biomarker types.

CONCLUSION

Panels of microRNAs and proteins are most promising biomarkers, while single biomarkers such as GFAP, IL-10 and individual miRNAs also hold promise. It is possible that panels are more accurate once these are involved in different, complementary cancer-related molecular pathways, because not all pathways may be dysregulated in cancer patients. As biomarkers seem to be increasingly dysregulated in patients with short survival, higher tumor grades and more pathological tumor types, it can be hypothesized that more pathways are dysregulated as the degree of malignancy of the glial tumor increases. Despite, none of the biomarkers found in the literature search seem to be currently ready for clinical implementation, and most of the studies report only preliminary application of the identified biomarkers. Hence, large-scale validation of currently identified and potential novel biomarkers to show clinical utility is warranted.

Role of neutrophil-lymphocyte ratio as a predictive factor of glioma tumor grade: A systematic review

Gliomas are the main type of intra-axial primary brain tumors. We performed a systematic review of studies on the neutrophil-to-lymphocyte ratio (NLR) and its role in the prognosis of patients with gliomas. An English-language literature-based search, using the PubMed and Biblioteca Virtual em Saúde databases, was conducted for papers published until May 2, 2020. The quality of the selected articles was stratified using the Newcastle-Ottawa scale's criteria. We found 137 publications for a query string. After applying the inclusion criteria, 13 articles were selected. Seven studies assessed overall survival and found high NLR values associated with poor overall survival. Six studies approached the issue of tumor grading and differential diagnosis and demonstrated that patients with high NLR values were diagnosed with high-grade gliomas. NLR is a low-cost method and an effective prognostic factor associated with tumor grading and OS in patients with gliomas.

Anti-inflammatory chemoprevention attenuates the phenotype in a mouse model of esophageal adenocarcinoma

Barrett´s Esophagus (BE) is the main known precursor condition of Esophageal Adenocarcinoma (EAC). BE is defined by the presence of metaplasia above the normal squamous columnar junction and has mainly been attributed to gastroesophageal reflux disease (GERD) and chronic reflux esophagitis. Thus, the rising incidence of EAC in the Western world is likely mediated by chronic esophageal inflammation, secondary to GERD in combination with environmental risk factors such as a Western diet and obesity. However, (at present) risk prediction tools and endoscopic surveillance have shown limited effectiveness. Chemoprevention as an adjunctive approach remains an attractive option to reduce the incidence of neoplastic disease. Here, we investigate the feasibility of chemopreventive approaches in BE and EAC via inhibition of inflammatory signaling in a transgenic mouse model of BE and EAC (L2-IL1B mice), with accelerated tumor formation on a high fat diet (HFD). L2-IL1B mice were treated with the IL-1 receptor antagonist Anakinra and the nonsteroidal anti-inflammatory drugs (NSAIDs) aspirin or Sulindac. Interleukin-1b antagonism reduced tumor progression in L2-IL1B mice with or without a HFD, while both NSAIDs were effective chemoprevention agents in the accelerated HFD fed L2-IL1B mouse model. Sulindac treatment also resulted in a marked change in the immune profile of L2-IL-1B mice. In summary, anti-inflammatory treatment of HFD-treated L2-IL1B mice acted protectively on disease progression. These results from a mouse model of BE support results from clinical trials that suggest that anti-inflammatory medication may be effective in the chemoprevention of EAC.

Inflammatory tumor microenvironment responsive neutrophil exosomes-based drug delivery system for targeted glioma therapy

Clinical treatment of malignant glioma remains a major challenge due to high infiltrative growth and chemotherapeutic resistance of tumors and the presence of the blood brain barrier (BBB). Advanced nanoplatforms that can efficiently cross the BBB and target to brain tumor are urgently needed. Encouraged by the intrinsic inflammatory chemotaxis and excellent BBB-crossing capability of neutrophils, a bioinspired neutrophil-exosomes (NEs-Exos) system for delivering loaded doxorubicin (DOX) drug for glioma treatment is proposed and systematically investigated. In vivo zebrafish and C6-Luc glioma-bearing mice models show that NEs-Exos carrying the drug rapidly penetrate the BBB and migrate into the brain. Additionally, a transwell BBB model and mouse brain inflammatory study show that NEs-Exos can respond chemotactically to inflammatory stimuli and target infiltrating tumor cells in inflamed brain tumors. Moreover, intravenous injection of NEs-Exos/DOX efficiently suppress tumor growth and prolong survival time in a glioma mouse model. On the basis of these results, NEs-Exos are confirmed to have neutrophil-like chemotactic function and BBB penetration. This novel NEs-Exos/DOX delivery platform represents a promising chemotherapeutic approach for clinical treatment of glioma and other solid tumor or brain diseases.

Regulation of MHC I Molecules in Glioblastoma Cells and the Sensitizing of NK Cells

Immunotherapy has been established as an important area in the therapy of malignant diseases. Immunogenicity sufficient for immune recognition and subsequent elimination can be bypassed by tumors through altered and/or reduced expression levels of major histocompatibility complex class I (MHC I) molecules. Natural killer (NK) cells can eliminate tumor cells in a MHC I antigen presentation-independent manner by an array of activating and inhibitory receptors, which are promising candidates for immunotherapy. Here we summarize the latest findings in recognizing and regulating MHC I molecules that affect NK cell surveillance of glioblastoma cells.

Influence of Dose on Neutrophil-Mediated Delivery of Nanoparticles for Tumor-Targeting Therapy Strategies

It is well known that neutrophil-mediated delivery of therapeutic agents is a promising method for treating tumors. However, owing to the limited number and limited uptake ability of neutrophils, determining a reasonable dose has become an urgent problem to be solved. Furthermore, the number of nanoparticles is far greater than the number of neutrophils at normal doses, which causes excessive nanoparticles to reach nontargeted organs or tissues, leading to serious adverse effects. To address these problems, a neutrophil-targeting delivery system (DiR-DADGC-L) based on DiR-labeled and butanedioic acid (DA)-linked 5-amino-3,5-dideoxy-D-Glycerol-D-galactonanulose-cholesterol conjugate (DADGC) was designed to improve the efficiency of hitchhiking neutrophils through the specific binding of sialic acid (SA) to L-selectin (SA-binding receptor, expressed on neutrophils). DiR-DADGC-L was prepared with favorable particle size and encapsulation efficiency (%EE) to deliver DiR into neutrophils. Subsequently, diverse doses of DiR-DADGC-L were injected intravenously into S180 tumor-bearing and cyclophosphamide-depleted (CTX-D) S180 tumor-bearing mice to evaluate the in vivo behavior of liposomes. The results verified the following: a) The content of DiR-DADGC-L in neutrophils accounts for approximately 14.5% of the content of DiR-DADGC-L in plasma, and the uptake capacity of neutrophils remains unchanged under different doses, and b) both neutrophils and the enhanced permeability and retention (EPR) effect might exert significant roles in tumor treatment. As for the neutrophil-mediated delivery system, higher doses are not necessarily appropriate, and a lower dose may achieve an unexpected effect. It will be wise to determine an optimum dose to improve delivery efficiency.

Biological Cells as Therapeutic Delivery Vehicles

One of the significant challenges remaining in the field of drug delivery is insufficient targeting of diseased tissues or cells. While efforts to perform targeted drug delivery by engineered nanoparticles have shown some success, there are underlying targeting, toxicity, and immunogenicity challenges. By contrast, live cells usually have innate targeting mechanisms, and can be used as drug-delivery vehicles to increase the efficiency with which a drug accumulates to act on the intended tissue. In some cases, when no native cell types exhibit the desired therapeutic phenotype, preferred outcomes can be achieved by genetically modifying and reprogramming cells with gene circuits. This review highlights recent advances in the use of cells to deliver therapeutics. Specifically, we discuss how red blood cells (RBCs), platelets, neutrophils, mesenchymal stem cells (MSCs), and bacteria have been utilized to advance drug delivery.

Tumor-Associated Neutrophils and Macrophages-Heterogenous but Not Chaotic

Tumor-associated macrophages (TAMs) and tumor-associated neutrophils (TANs) have been extensively studied. Their pleotropic roles were observed in multiple steps of tumor progression and metastasis, and sometimes appeared to be inconsistent across different studies. In this review, we collectively discussed many lines of evidence supporting the mutual influence between cancer cells and TAMs/TANs. We focused on how direct interactions among these cells dictate co-evolution involving not only clonal competition of cancer cells, but also landscape shift of the entire tumor microenvironment (TME). This co-evolution may take distinct paths and contribute to the heterogeneity of cancer cells and immune cells across different tumors. A more in-depth understanding of the cancer-TAM/TAN co-evolution will shed light on the development of TME that mediates metastasis and therapeutic resistance.

Microglia/macrophages express alternative proangiogenic factors depending on granulocyte content in human glioblastoma

Myeloid cells are an inherent part of the microenvironment of glioblastoma multiforme (GBM). There is growing evidence for their participation in mechanisms of tumor escape, especially in the development of resistance following initially promising anti-VEGF/VEGFR treatment. Thus, we sought to define the capability of myeloid cells to contribute to the expression of proangiogenic molecules in human GBM. We investigated GBM specimens in comparison with anaplastic astrocytoma (WHO grade III) and epilepsy patient samples freshly obtained from surgery. Flow cytometric analyses revealed two distinct CD11b⁺ CD45⁺ cell populations in GBM tissues, which were identified as microglia/macrophages and granulocytes. Due to varied granulocyte influx, GBM samples were subdivided into groups with low (GBM-lPMNL) and high (GBM-hPMNL) numbers of granulocytes (polymorphonuclear leukocytes; PMNL), which were related to activation of the microglia/macrophage population. Microglia/macrophages of the GBM-lPMNL group were similar to those of astrocytoma specimens, but those of GBM-hPMNL tissues revealed an altered phenotype by expressing high levels of CD163, TIE2, HIF1α, VEGF, CXCL2 and CD13. Although microglia/macrophages represented the main source of alternative proangiogenic factors, additionally granulocytes participated by production of IL8 and CD13. Moreover, microglia/macrophages of the GBM-hPMNL specimens were highly associated with tumor blood vessels, accompanied by remodeling of the vascular structure. Our data emphasize that tumor-infiltrating myeloid cells might play a crucial role for limited efficacy of anti-angiogenic therapy bypassing VEGF-mediated pathways through expression of alternative proangiogenic factors. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Systemic Inflammation Response Index Predicts Survival Outcomes in Glioblastoma Multiforme Patients Treated with Standard Stupp Protocol

Objectives

We endeavored to retrospectively assess the prognostic merit of pretreatment systemic immune response index (SIRI) in glioblastoma multiforme (GBM) patients who underwent postoperative partial brain radiotherapy (RT) and concurrent plus adjuvant temozolomide (TMZ), namely, the Stupp protocol.

Methods

The records of 181 newly diagnosed GBM patients who received the postoperative Stupp protocol were retrospectively analyzed. The SIRI value for each eligible patient was calculated by utilizing the platelet, neutrophil, and lymphocyte measures obtained on the first day of treatment: SIRI = Neutrophils × Monocytes/Lymphocytes. The ideal cutoff values for SIRI connected with the progression-free- (PFS) and overall survival (OS) results were methodically searched through using the receiver operating characteristic (ROC) curve analysis. Primary and secondary end-points constituted the potential OS and PFS distinctions among the SIRI groups, respectively.

Results

The ROC curve analysis labeled the ideal SIRI cutoffs at 1.74 (Area under the curve (AUC): 74.9%; sensitivity: 74.2%; specificity: 71.4%) and 1.78 (AUC: 73.6%; sensitivity: 73.1%; specificity: 70.8%) for PFS and OS status, individually. The SIRI cutoff of 1.78 of the OS status was chosen as the common cutoff for the stratification of the study population (Group 1: SIRI ≤ 1.78 (N = 96) and SIRI > 1.78 (N = 85)) and further comparative PFS and OS analyses. Comparisons between the two SIRI cohorts manifested that the SIRI ≤ 1.78 cohort had altogether significantly superior median PFS (16.2 versus 6.6 months; P < 0.001) and OS (22.9 versus 12.2 months; P < 0.001) than its SIRI > 1.78 counterparts. The results of multivariate Cox regression analyses ratified the independent and significant alliance between a low SIRI and longer PFS (P < 0.001) and OS (P < 0.001) durations, respectively.

Conclusions

Present results firmly counseled the pretreatment SIRI as a novel, sound, and independent predictor of survival outcomes in newly diagnosed GBM patients intended to undergo postoperative Stupp protocol.

Tenascin-C Function in Glioma: Immunomodulation and Beyond

First identified in the 1980s, tenascin-C (TNC) is a multi-domain extracellular matrix glycoprotein abundantly expressed during the development of multicellular organisms. TNC level is undetectable in most adult tissues but rapidly and transiently induced by a handful of pro-inflammatory cytokines in a variety of pathological conditions including infection, inflammation, fibrosis, and wound healing. Persistent TNC expression is associated with chronic inflammation and many malignancies, including glioma. By interacting with its receptor integrin and a myriad of other binding partners, TNC elicits context- and cell type-dependent function to regulate cell adhesion, migration, proliferation, and angiogenesis. TNC operates as an endogenous activator of toll-like receptor 4 and promotes inflammatory response by inducing the expression of multiple pro-inflammatory factors in innate immune cells such as microglia and macrophages. In addition, TNC drives macrophage differentiation and polarization predominantly towards an M1-like phenotype. In contrast, TNC shows immunosuppressive function in T cells. In glioma, TNC is expressed by tumor cells and stromal cells; high expression of TNC is correlated with tumor progression and poor prognosis. Besides promoting glioma invasion and angiogenesis, TNC has been found to affect the morphology and function of tumor-associated microglia/macrophages in glioma. Clinically, TNC can serve as a biomarker for tumor progression; and TNC antibodies have been utilized as an adjuvant agent to deliver anti-tumor drugs to target glioma. A better mechanistic understanding of how TNC impacts innate and adaptive immunity during tumorigenesis and tumor progression will open new therapeutic avenues to treat brain tumors and other malignancies.

Systemic Inflammatory Indicators as Prognosticators in Glioblastoma Patients: A Comprehensive Meta-Analysis

Background: Inflammation plays an important role in tumorigenesis. Previous studies have reported the prognostic value of several peripheral inflammatory markers in glioma patients, including the neutrophil-to-lymphocyte ratio (NLR). However, it still remains unclear whether inflammatory markers can independently predict the prognosis of glioblastoma (GBM) patients. The present study aims to explore the prognostic value of systemic inflammatory markers, including neutrophils, lymphocytes, platelets, the NLR, and the platelet-to-lymphocyte ratio (PLR), in patients with GBM.

Methods: A comprehensive systemic search and review was performed using the PubMed, EMBASE, and Cochrane Library databases to identify all the relevant literature (published before June 30, 2020) that evaluated the association between any of these inflammatory markers and survival in GBM.

Results: There were 2 (634 patients), 3 (723 patients), 2 (237 patients), 8 (1,225 patients), and 3 (505 patients) studies examining the correlation of survival with neutrophils, lymphocytes, platelets, the NLR, and the PLR, respectively. An elevated NLR and elevated neutrophil and platelet counts were associated with worse overall survival (OS) in GBM patients (NLR: hazard ratio [HR] = 1.63, 95% confidence interval [CI]: 1.23–2.15, p = 0.0007; neutrophil count: HR = 1.46, 95% CI:1.16–1.83, p = 0.001; platelet count: HR = 1.58, 95% CI: 1.42–1.77, p < 0.00001). However, there was no significant association between the PLR or the absolute lymphocyte count and OS in GBM patients.

Conclusion: The NLR and the absolute neutrophil and platelet counts may be valuable and convenient peripheral inflammatory markers to evaluate the prognosis of GBM patients. Further prospective studies are needed to verify its reliability.

Magnetic resonance imaging-based radiomic features for extrapolating infiltration levels of immune cells in lower-grade gliomas

PURPOSE

To extrapolate the infiltration levels of immune cells in patients with lower-grade gliomas (LGGs) using magnetic resonance imaging (MRI)-based radiomic features.

METHODS

A retrospective dataset of 516 patients with LGGs from The Cancer Genome Atlas (TCGA) database was analysed for the infiltration levels of six types of immune cells using Tumor IMmune Estimation Resource (TIMER) based on RNA sequencing data. Radiomic features were extracted from 107 patients whose pre-operative MRI data are available in The Cancer Imaging Archive; 85 and 22 of these patients were assigned to the training and testing cohort, respectively. The least absolute shrinkage and selection operator (LASSO) was applied to select optimal radiomic features to build the radiomic signatures for extrapolating the infiltration levels of immune cells in the training cohort. The developed radiomic signatures were examined in the testing cohort using Pearson's correlation.

RESULTS

The infiltration levels of B cells, CD4+ T cells, CD8+ T cells, macrophages, neutrophils and dendritic cells negatively correlated with overall survival in the 516 patient cohort when using univariate Cox's regression. Age, Karnofsky Performance Scale, WHO grade, isocitrate dehydrogenase mutant status and the infiltration of neutrophils correlated with survival using multivariate Cox's regression analysis. The infiltration levels of the 6 cell types could be estimated by radiomic features in the training cohort, and their corresponding radiomic signatures were built. The infiltration levels of B cells, CD8+ T cells, neutrophils and macrophages estimated by radiomics correlated with those estimated by TIMER in the testing cohort. Combining clinical/genomic features with the radiomic signatures only slightly improved the prediction of immune cell infiltrations.

CONCLUSION

We developed MRI-based radiomic models for extrapolating the infiltration levels of immune cells in LGGs. Our results may have implications for treatment planning.

Neutrophil-to-Lymphocyte Ratio and Its Changes are Related to Grade II-IV Glioma Recurrence

Objective

To explore whether the neutrophil-to-lymphocyte ratio (NLR) and its changes are related to tumor recurrence in grade II-IV glioma patients.

Methods

One hundred patients who underwent two surgeries (first for diagnosis and the second for recurrence) were retrospectively analyzed. Complete blood count was obtained preoperatively before any treatment. Basic NLR (before the first surgery) and NLR changes were calculated. Tumor recurrence was evaluated by progression-free survival (PFS) using the Kaplan-Meier method. Univariate and multivariate Cox regression analyses were used to determine the potential prognostic factors for PFS.

Results

The PFS of patients with high basic NLR (≥4) (median 9 months) was shorter than that of patients with low basic NLR (<4) (median 23 months) (P = 0.004). Univariate and multivariate analyses both showed that basic NLR (before the first surgery) (≥4 vs <4) was an independent predictor of PFS (P = 0.011). The PFS is also varied with NLR changes before two surgeries (P < 0.05). The PFS of patients with two low NLR (<4) at both initial surgical resection and section for tumor recurrence had the longest PSF. The patients with two high NLR (≥4) at both initial surgical resection and section for tumor recurrence had the shortest PSF. The patients with one high NLR (≥4) at initial surgical resection or section for tumor recurrence had an average PSF. Multivariate analysis showed that the change of NLR was of prognostic significance independent of glioma grade.

Conclusion

We showed both basic NLR and NLR changes could predict the recurrence of glioma, but the change of NLR is more accurate than that of basic NLR. The current research not only provides a simple and feasible method for clinical judgment of glioma recurrence but also provides a new idea for exploring the mechanism of glioma recurrence.

Pre-operative hematological markers as predictive factors for overall survival and progression free survival in glioblastomas

INTRODUCTION

Several hematological factors, such as neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), prognostic nutrition index (PNI) and albumin-to-globulin ratio (AGR), have been highlighted as systemic worse prognostic parameters for the outcome in gliomas. The aim of this study is to identify some pre-operative routinely blood tests as predictive parameters for the Overall Survival (OS) and Progression Free Survival (PFS) in glioblastoma (GBM).

MATERIALS AND METHODS

From January 2013 to April 2019, 124 patients operated for glioblastoma were analyzed. Data were collected regarding age, sex, Karnofsky performance status (KPS), IDH status, the extent of resection (EOR) and adjuvant therapy. The hematological parameters were collected at admission: neutrophils, lymphocytes and platelets, hemoglobin, lactate dehydrogenase, albumin, NLR, PLR, AGR and PNI. The OS and the PFS were considered as the end-point for the evaluation of the predictive factors.

RESULTS

A pre-operative neutrophil count > 7 × 10⁹/L was a worse prognostic factor for OS and PFS at univariate analysis (p = 0.004 and p = 0.025), as well as hypo-albuminemia. Thrombocytosis, lymphopenia and NLR > 4 were associated to a worse OS, at uni- and multivariate analysis, resulting as poor predictive parameters, independently to EOR, the IDH mutation and the adjuvant therapy.

CONCLUSIONS

Still nowadays there are no sensitive or specific hematological markers which are routinely applied for detecting and monitoring the treatment-response and the prognosis of glioblastoma. In our study, a pre-operative low cost and widely used blood markers, such as NLR, lymphocytes and platelets could be predictable prognostic factors for the Overall Survival of patients affected by glioblastomas.

Pediatric pan-central nervous system tumor analysis of immune-cell infiltration identifies correlates of antitumor immunity

Immune-therapy is an attractive alternative therapeutic approach for targeting central nervous system (CNS) tumors and the constituency of the Tumor Immune Microenvironment (TIME) likely to predict patient response. Here, we describe the TIME of >6000 primarily pediatric CNS tumors using a deconvolution approach (methylCIBERSORT). We produce and validate a custom reference signature defining 11 non-cancer cell types to estimate relative proportions of infiltration in a panCNS tumor cohort spanning 80 subtypes. We group patients into three broad immune clusters associated with CNS tumor types/subtypes. In cohorts of medulloblastomas (n = 2325), malignant rhabdoid tumors (n = 229) and pediatric high-grade gliomas (n = 401), we show significant associations with molecular subgroups/subtypes, mutations, and prognosis. We further identify tumor-specific immune clusters with phenotypic characteristics relevant to immunotherapy response (i.e. Cytolytic score, PDL1 expression). Our analysis provides an indication of the potential future therapeutic and prognostic possibilities of immuno-methylomic profiling in pediatric CNS tumor patients that may ultimately inform approach to immune-therapy.

Neutrophil depletion enhances the therapeutic effect of PD-1 antibody on glioma

Tumor-infiltrating neutrophils (TINs), the predominant leukocytes in the tumor microenvironment, are important for cancer-related immunosuppression. Combinations of multiple immune checkpoint inhibitors can significantly improve outcomes in murine glioma models. Here, we investigated TIN levels in human glioma samples and tested the antitumor efficacy of neutrophil depletion alone or in combination with an anti-programmed death 1 (PD-1) antibody. To investigate the clinical relevance, we determined the correlation between tumor grade or survival and TIN levels in 202 resected glioma specimens. TCGA and CGGA data were used to validate the results and analyze the biological functions of TINs in gliomas. An orthotopic xenograft glioma mouse model was used to study the therapeutic effect of anti-PD-1 and/or anti-ly6G. Decreased TIN levels correlated with lower grades, mutant isocitrate dehydrogenase, and favorable prognosis, which was validated by CGGA and TCGA dataset results. Bioinformatics analysis revealed that TINs are mainly involved in angiogenic, inflammatory, and interferon-γ responses in gliomas. TINs were positively correlated with programmed death ligand-1 expression. In xenograft models, combined anti-PD-1 and neutrophil depletion therapy significantly inhibited tumor growth and promoted survival. This study demonstrates that TINs were related to glioma tumorigenesis. Targeting neutrophils could thus enhance the therapeutic effect of PD-1 blockade for gliomas.

P2X7 receptor antagonism inhibits tumour growth in human high-grade gliomas

Gliomas, the most common primary brain cancer, are highly infiltrative and extremely difficult to treat. Despite advancements, current treatment is limited, with patients surviving for a median of 14-15 months post-diagnosis. Previous research has demonstrated the upregulation of a purinergic receptor, P2X7R, in human gliomas. P2X7R is expressed on both glioma cells and microglia within the glioma microenvironment. It is hypothesized that P2X7R contributes to tumour growth and proliferation via immune-mediated mechanisms involving tumour cells and surrounding microglia. We sought to elucidate the role of P2X7R in a human glioblastoma cell line (U251) and on surgically resected human glioma samples. We treated U251 and human glioma cultures for 72 h with P2X7R antagonists, Brilliant Blue G (BBG), oxidized ATP (oATP) and AZ10606120. Cell counting via fluorescence confocal microscopy was conducted to assess tumour proliferation. We observed no significant reductions in tumour cell numbers following P2X7R antagonism with BBG (20 μM) and oATP (250 μM) in both U251 cells and human glioma samples. Interestingly, there was a significant reduction in tumour cell number in both U251 cells (p = 0.0156) and human glioma samples (p = 0.0476) treated with varying concentrations of AZ10606120. When compared with the conventional chemotherapeutic agent, temozolomide, AZ10606120 was also found to more effectively inhibit tumour proliferation in U251 cells (p < 0.0001). Our pilot results demonstrate a potential trophic role of P2X7R where its inhibition by AZ10606120, a potent antagonist, hinders glioma growth directly or through the inactivation of microglia. This sheds new light on P2X7R as a therapeutic target for human gliomas.

Is medulloblastoma associated with systemic immunomodulation? - A comparative analysis of preoperative inflammatory markers

Background:

We attempt to compare preoperative inflammatory markers among children with medulloblastoma and pilocytic astrocytoma and establish their diagnostic efficacy to distinguish these tumors.

Methods:

Children (<18 years) with biopsy-proven medulloblastoma and pilocytic astrocytoma operated at our institute from January 2012 to January 2018 were enrolled in this study. The hematological parameters were compared between the two groups and with healthy controls. Children with a history of disease or medications that may confound these parameters were excluded from the study. Receiver operator characteristic curves were made to assess the diagnostic accuracy of markers found to be significant.

Results:

Patients with medulloblastoma were found to have higher neutrophil-lymphocyte ratio (NLR), derived neutrophil-lymphocyte ratio (dNLR), platelet-lymphocyte ratio (PLR), and platelet counts compared with pilocytic astrocytoma. Absolute lymphocyte count (ALC) was significantly lower in medulloblastoma group as compared to healthy controls but not with pilocytic astrocytoma. NLR and dNLR demonstrated maximum diagnostic accuracy in distinguishing patients with medulloblastoma from healthy controls and pilocytic astrocytoma. Using a cutoff of 2.45 for NLR distinguishes medulloblastoma from healthy controls as well as pilocytic astrocytoma with a sensitivity of 75.5% and specificity of 66.7%. Similarly, dNLR cutoff of 1.47 distinguishes medulloblastoma from healthy controls with a sensitivity of 83% and specificity of 76% and a cutoff of 1.53 distinguishes medulloblastoma from pilocytic astrocytoma with a sensitivity of 81.1% and specificity of 81.8%. Combination of NLR and dNLR performed only marginally better than individual variables with area under the curve being 0.856 for medulloblastoma versus healthy controls and 0.86 for medulloblastoma versus pilocytic astrocytoma.

Conclusion:

NLR and dNLR can be used as a preoperative predictive marker in medulloblastoma. There is decreased ALC in patients with medulloblastoma contributing to raised NLR and dNLR suggestive of systemic immunosuppression.

LINC01116 promotes tumor proliferation and neutrophil recruitment via DDX5-mediated regulation of IL-1β in glioma cell

Tumor-associated neutrophils (TANs) are important inflammatory infiltrating cells in the tumor microenvironment and are closely related to the development of human tumor. However, the underlying mechanism of TANs recruiting to glioma remains unknown. Herein, we identified that LINC01116 was significantly upregulated in glioma, and positively correlated with clinical malignancy and survival prognosis. LINC01116 regulated the progression of glioma in vitro and in vivo. RNA-seq analysis demonstrated that LINC01116 knockdown affected the expression of IL-1β, which promoted glioma proliferation and neutrophil recruitment. Furthermore, the co-culture of glioma cells and neutrophils showed that the accumulation of TANs promoted tumor proliferation via producing a host of cytokines. Mechanistically, LINC01116 activated IL-1β expression by recruiting the transcriptional regulator DDX5 to the IL-1β promoter. Our findings reveal that LINC01116 can promote glioma proliferation and neutrophil recruitment by regulating IL-1β, and may be served as a novel target for glioma therapy and prognosis.

Role of Neutrophils and Myeloid-Derived Suppressor Cells in Glioma Progression and Treatment Resistance

Recent efforts in brain tumor research have been directed towards the modulation of the immune system for therapeutic interventions. Several human cancers, including gliomas, are infiltrated with immune cell types-including neutrophils and myeloid-derived suppressor cells-that contribute to tumor progression, invasiveness, and treatment resistance. The role of tumor-associated neutrophils and myeloid-derived suppressor cells in cancer biology remains elusive, as these cells can exert a multitude of pro-tumor and antitumor effects. In this review, we provide the current understanding and novel insights on the role of neutrophils and myeloid-derived suppressor cells in glioma progression and treatment resistance, as well as the mechanisms of pleiotropic behaviors in these cells during disease progression, with an emphasis on possible strategies to reprogram these cells towards their antitumor actions.

Cell-mediated and cell membrane-coated nanoparticles for drug delivery and cancer therapy

Nanotechnology-based drug delivery platforms have been developed over the last two decades because of their favorable features in terms of improved drug bioavailability and stability. Despite recent advancement in nanotechnology platforms, this approach still falls short to meet the complexity of biological systems and diseases, such as avoiding systemic side effects, manipulating biological interactions and overcoming drug resistance, which hinders the therapeutic outcomes of the NP-based drug delivery systems. To address these issues, various strategies have been developed including the use of engineered cells and/or cell membrane-coated nanocarriers. Cell membrane receptor profiles and characteristics are vital in performing therapeutic functions, targeting, and homing of either engineered cells or cell membrane-coated nanocarriers to the sites of interest. In this context, we comprehensively discuss various cell- and cell membrane-based drug delivery approaches towards cancer therapy, the therapeutic potential of these strategies, and the limitations associated with engineered cells as drug carriers and cell membrane-associated drug nanocarriers. Finally, we review various cell types and cell membrane receptors for their potential in targeting, immunomodulation and overcoming drug resistance in cancer.

Neutrophil-to-Lymphocyte Ratio: Can It Be Used as an Adjunct Tool to Predict Histopathological Grade of Brain Tumor?

Background Since histopathology is available only after surgery, clinical condition and radiological characters of the tumor are important factors on which a clinician counsels the patient of brain tumor to take a decision regarding the management. Neutrophil lymphocyte ratio (NLR), a marker of inflammation can be used as a prognostic marker to predict the survival in high-grade gliomas and metastases. We evaluated the utility of NLR as an adjunct tool in predicting the histopathological grade of brain tumors.

Materials and Methods One hundred sixteen patients with a diagnosis of brain tumors planned for surgical excision or biopsy were enrolled in the study. NLR was estimated in the preoperative blood sample. Patients were grouped into low- and highgrade brain tumors and their mean NLRs were analyzed. Similar evaluation was carried out between the intra- and extra-axial tumors.

Results Mean age of the study group was 40.14 years with 61 males. Seventy-eight patients had low-grade tumor and 38 patients had high-grade tumor. Sixty patients had extra-axial tumors and 56 patients had intra-axial tumors. The mean NLR of low-grade tumors was 1.68 ± 0.53 and that of high-grade tumors was 3.12 ± 0.74. NLR > 2.4 can be used to identify high-grade brain tumors with a sensitivity of 80%, specificity of 92%, positive predictive value of 82.1%, negative predictive value of 91%, an excellent impact with likelihood ratio (+) of 10.1, and an odds ratio of 54.1. The mean NLR of extra-axial tumors was 1.68 + 0.62 and that of intra-axial tumors was 2.64 ± 0.91. These observations were statistically significant with p -value < 0.05.

Conclusions NLR is an easily available and inexpensive marker of systemic inflammation, which varies across different histopathological grades of brain tumors. Mean NLR is higher in high-grade tumors and also intra-axial tumors with a cutoff value of NLR > 2.4 and > 2.0, respectively.

The Brain Entangled: The Contribution of Neutrophil Extracellular Traps to the Diseases of the Central Nervous System

Under normal conditions, neutrophils are restricted from trafficking into the brain parenchyma and cerebrospinal fluid by the presence of the brain–blood barrier (BBB). Yet, infiltration of the central nervous system (CNS) by neutrophils is a well-known phenomenon in the course of different pathological conditions, e.g., infection, trauma or neurodegeneration. Different studies have shown that neutrophil products, i.e., free oxygen radicals and proteolytic enzymes, play an important role in the pathogenesis of BBB damage. It was recently observed that accumulating granulocytes may release neutrophil extracellular traps (NETs), which damage the BBB and directly injure surrounding neurons. In this review, we discuss the emerging role of NETs in various pathological conditions affecting the CNS.

Microenvironmental Heterogeneity in Brain Malignancies

Brain tumors are among the deadliest malignancies. The brain tumor microenvironment (TME) hosts a unique collection of cells, soluble factors, and extracellular matrix components that regulate disease evolution of both primary and metastatic brain malignancies. It is established that macrophages and other myeloid cells are abundant in the brain TME and strongly correlate with aggressive phenotypes and distinct genetic signatures, while lymphoid cells are less frequent but are now known to have a pronounced effect on disease progression. Different types of brain tumors vary widely in their microenvironmental contexture, and the proportion of various stromal components impacts tumor biology. Indeed, emerging evidence suggests an intimate link between the molecular signature of tumor cells and the composition of the TME, shedding light on the mechanisms which underlie microenvironmental heterogeneity in brain cancer. In this review, we discuss the association between TME composition and the diverse molecular profiles of primary gliomas and brain metastases. We also discuss the implications of these associations on the efficacy of immunotherapy in brain malignancies. An appreciation for the causes and functional consequences of microenvironmental heterogeneity in brain cancer will be of crucial importance to the rational design of microenvironment-targeted therapies for these deadly diseases.

Multidimensional communication in the microenvirons of glioblastoma

Glioblastomas are heterogeneous and invariably lethal tumours. They are characterized by genetic and epigenetic variations among tumour cells, which makes the development of therapies that eradicate all tumour cells challenging and currently impossible. An important component of glioblastoma growth is communication with and manipulation of other cells in the brain environs, which supports tumour progression and resistance to therapy. Glioblastoma cells recruit innate immune cells and change their phenotype to support tumour growth. Tumour cells also suppress adaptive immune responses, and our increasing understanding of how T cells access the brain and how the tumour thwarts the immune response offers new strategies for mobilizing an antitumour response. Tumours also subvert normal brain cells - including endothelial cells, neurons and astrocytes - to create a microenviron that favours tumour success. Overall, after glioblastoma-induced phenotypic modifications, normal cells cooperate with tumour cells to promote tumour proliferation, invasion of the brain, immune suppression and angiogenesis. This glioblastoma takeover of the brain involves multiple modes of communication, including soluble factors such as chemokines and cytokines, direct cell-cell contact, extracellular vesicles (including exosomes and microvesicles) and connecting nanotubes and microtubes. Understanding these multidimensional communications between the tumour and the cells in its environs could open new avenues for therapy.

Preoperative Neutrophil/Lymphocyte Ratio Is an Independent Prognostic Biomarker in Patients with Low-Grade Gliomas

BACKGROUND

There are no standardized criteria to predict the prognosis of patients with low-grade gliomas. Therefore, novel prognostic biomarkers that can guide follow-up schedules and therapeutic approaches urgently are required in patients with low-grade gliomas.

METHODS

One hundred nineteen patients with World Health Organization (WHO) II gliomas were recruited between January 2010 and December 2016 from Xiangya Hospital for this study. We collected neutrophil and lymphocyte values from the full blood counts measured 24 h before surgery. Neutrophil-to-lymphocyte ratios (NLRs) were then calculated. The significance of the NLR was determined based on a nonparametric test. The Kaplan-Meier method was used to estimate survival rates. The influence of the NLR on progression-free survival and overall survival was evaluated using univariate and multivariate Cox proportional hazards models.

RESULTS

Preoperative NLRs were upregulated in patients with WHO II gliomas who relapsed or died. Preoperative NLRs were also significantly correlated with age, preoperative neutrophil values, and preoperative lymphocyte values. Compared with the low preoperative NLR group, patients with WHO II gliomas in the high preoperative NLR group had significantly higher relapse and lower survival rates. In addition, the preoperative NLR and tumor type were independent prognostic parameters of progression-free survival for WHO II gliomas, whereas only the preoperative NLR was an independent prognostic parameter of overall survival for WHO II gliomas.

CONCLUSIONS

High preoperative NLRs were significantly associated with greater relapse and poor prognosis in patients with WHO II gliomas.

Immunity, Hypoxia, and Metabolism-the Ménage à Trois of Cancer: Implications for Immunotherapy

It is generally accepted that metabolism is able to shape the immune response. Only recently we are gaining awareness that the metabolic crosstalk between different tumor compartments strongly contributes to the harsh tumor microenvironment (TME) and ultimately impairs immune cell fitness and effector functions. The major aims of this review are to provide an overview on the immune system in cancer; to position oxygen shortage and metabolic competition as the ground of a restrictive TME and as important players in the anti-tumor immune response; to define how immunotherapies affect hypoxia/oxygen delivery and the metabolic landscape of the tumor; and vice versa, how oxygen and metabolites within the TME impinge on the success of immunotherapies. By analyzing preclinical and clinical endeavors, we will discuss how a metabolic characterization of the TME can identify novel targets and signatures that could be exploited in combination with standard immunotherapies and can help to predict the benefit of new and traditional immunotherapeutic drugs.

Neutrophil-lymphocyte ratio dynamics are useful for distinguishing between recurrence and pseudoprogression in high-grade gliomas

Objective

Distinguishing recurrence and pseudoprogression is a major challenge in the clinical practice of treatment for high-grade gliomas (HGGs). The neutrophil-lymphocyte ratio (NLR) has been reported to be closely related to survival in HGGs. We aimed to assess the predictive value of NLR in the differential diagnosis of recurrence and pseudoprogression.

Materials and Methods

A total of 135 patients with histologically confirmed HGGs were studied. All patients underwent focal radiotherapy and concomitant temozolomide (TMZ), followed by 6 cycles of TMZ if MRI showed no progressive enlargement of contrast-enhancing lesions. MRI evaluation was taken 4 weeks after concurrent chemoradiotherapy and then every 2 months later. NLR was calculated at 4 time points of preoperation, before concurrent RT-TMZ (pretreatment), 4 weeks following completion of RT-TMZ, and MRI showed lesion enlarged or treatment completed.

Results

In 135 patients, 47 (34.8%) were found to be pseudoprogression (PsPD), and 28 (20.7%) were early disease progression (ePD). The mean pretreatment and post-treatment NLR were 4.2±2.1 and 5.1±3.5, respectively. The median overall survival in the PsPD group (25.2 months) was significantly longer than in the ePD (15.4 months) and no progression group (nPD) (21.6 months) (p<0.001). Overall survival was significantly shorter in the baseline NLR≥4 cohort compared with NLR<4 (p=0.03), but no significant difference was found between PsPD and ePD (p=0.197). Patients with decreased NLR showed significantly longer survival than no decreased group (p<0.001), and decreased NLR was found to be a significant difference between PsPD and ePD (p=0.022). Univariate and multivariate logistic regression analyses suggested that decreased NLR was an independent prognosis factor (p=0.031).

Conclusion

Decreased NLR is an independent prognostic factor and is useful for distinguishing between recurrence and pseudoprogression in HGGs.

Brainwashed by extracellular vesicles: the role of extracellular vesicles in primary and metastatic brain tumour microenvironment

Brain malignancies, including primary and metastatic brain tumours, are often associated with high mortality, reflecting a need for more effective diagnostics and therapeutics. Despite the different cells of origin, primary and metastatic brain tumours share the same microenvironment, which affects the survival mechanisms adopted by these tumours. Elucidating the mechanisms by which primary and metastatic brain tumours interact with the brain microenvironment can uncover potential targets for clinical applications. Extracellular vesicles have been recognized as intercellular communicators that can contribute to cancer progression and have shown promise as potential cancer biomarkers and therapeutics. Here, we outline the contribution of extracellular vesicles in the tumour–microenvironment interactions in primary and metastatic brain tumours with the goal of providing a guide for future translational research in this area.

The prognostic role of preoperative systemic immune-inflammation index and albumin/globulin ratio in patients with newly diagnosed high-grade glioma

OBJECTIVE

Preoperative systemic immune-inflammation index (SII) and the albumin/globulin ratio (AGR) have been used as prognostic markers in many malignancies. This study was conducted to evaluate the clinical significance of the preoperative SII and AGR in high-grade glioma (HGG) patients.

PATIENTS AND METHODS

A total of 169 patients with newly diagnosed HGG were enrolled in the current study. Overall survival (OS) of these patients was estimated by Kaplan-Meier analyses. Univariate and multivariate Cox regression analyses were performed to examine the relationships between OS and prognostic variables in patients with HGG.

RESULTS

The cut-off values for SII and AGR were 324.38 × 10⁹/L and 1.35, respectively. An inverse correlation was observed between SII and AGR. The Kaplan-Meier survival analyses demonstrated that high SII and low AGR were associated with poor OS of patients with HGG (P = 0.002 and P = 0.012, respectively). Multivariate analyses revealed that both SII (HR 1.641, 95% CI: 1.071-2.515; P = 0.023) and AGR (HR 0.566, 95% CI: 0.335-0.956; P = 0.033) were independent predictive indicators of OS of HGG patients.

CONCLUSIONS

In conclusion, this study demonstrated that high SII and low AGR values may serve as promising prognostic markers to identify HGG patients with poor prognosis.

Isocitrate dehydrogenase 1 mutation is associated with reduced levels of inflammation in glioma patients

Background: Glioma patients with mutant isocitrate dehydrogenase have improved survival; this could be in part due to the suppressive effect of mutant IDH on the level of chronic inflammation. This study aimed to prospectively analyze the association of IDH1 mutation status with preoperative levels of blood inflammatory markers: neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), C-reactive protein (CRP), and red cell distribution width (RDW) in gliomas. Patients and methods: Receiver operating characteristic curves for cutoff value determination, various bivariate tests, and survival analyses (Kaplan-Meier curves and Cox regression) were performed. Results: Patients with mutant IDH1 had reduced levels of NLR (P<0.032) and CRP (P<0.008). Moreover, these patients showed better median overall survival compared to those without IDH1 mutation (P<0.000). In univariate analysis, IDH1 mutation status (P<0.000), NLR (P<0.000), PLR (P<0.008), and CRP (P<0.001) were among the factors associated with survival. By multivariate analysis, IDH1 mutation (P<0.044) and NLR<2.65 (P<0.022) remained independent factors associated with better survival; other independent variables were tumor grade (P<0.000) and location in noneloquent area (P<0.015). Conclusion: The obtained results show that IDH1 mutation is associated with lower levels of chronic inflammation that could account for an improved prognosis in this group of patients.

FcγRIIIb Restricts Antibody-Dependent Destruction of Cancer Cells by Human Neutrophils

The function of the low-affinity IgG-receptor FcγRIIIb (CD16b), which is uniquely and abundantly expressed on human granulocytes, is not clear. Unlike the other Fcγ receptors (FcγR), it is a glycophosphatidyl inositol (GPI) -anchored molecule and does not have intracellular signaling motifs. Nevertheless, FcγRIIIb can cooperate with other FcγR to promote phagocytosis of antibody-opsonized microbes by human neutrophils. Here we have investigated the role of FcγRIIIb during antibody-dependent cellular cytotoxicity (ADCC) by neutrophils toward solid cancer cells coated with either trastuzumab (anti-HER2) or cetuximab (anti-EGFR). Inhibiting FcγRIIIb using CD16-F(ab')₂ blocking antibodies resulted in substantially enhanced ADCC. ADCC was completely dependent on FcγRIIa (CD32a) and the enhanced ADCC seen after FcγRIIIb blockade therefore suggested that FcγRIIIb was competing with FcγRIIa for IgG on the opsonized target cells. Interestingly, the function of neutrophil FcγRIIIb as a decoy receptor was further supported by using neutrophils from individuals with different gene copy numbers of FCGR3B causing different levels of surface FcγRIIIb expression. Individuals with one copy of FCGR3B showed higher levels of ADCC compared to those with two or more copies. Finally, we show that therapeutic antibodies intended to improve FcγRIIIa (CD16a)-dependent natural killer (NK) cell ADCC due to the lack of fucosylation on the N-linked glycan at position N297 of the IgG₁ heavy chain Fc-region, show decreased ADCC as compared to regularly fucosylated antibodies. Together, these data confirm FcγRIIIb as a negative regulator of neutrophil ADCC toward tumor cells and a potential target for enhancing tumor cell destruction by neutrophils.

Emerging blood–brain-barrier-crossing nanotechnology for brain cancer theranostics

The advancements, perspectives, and challenges in blood–brain-barrier (BBB)-crossing nanotechnology for effective brain tumor delivery and highly efficient brain cancer theranostics.

MR imaging tracking of inflammation-activatable engineered neutrophils for targeted therapy of surgically treated glioma

Cell-based drug delivery systems have shown promising capability for tumor-targeted therapy owing to the intrinsic tumor-homing and drug-carrying property of some living cells. However, imaging tracking of their migration and bio-effects is urgently needed for clinical application, especially for glioma. Here, we report the inflammation-activatable engineered neutrophils by internalizing doxorubicin-loaded magnetic mesoporous silica nanoparticles (ND-MMSNs) which can provide the potential for magnetic resonance (MR) imaging tracking of the drug-loaded cells to actively target inflamed brain tumor after surgical resection of primary tumor. The phagocytized D-MMSNs possess high drug loading efficiency and do not affect the host neutrophils’ viability, thus remarkably improving intratumoral drug concentration and delaying relapse of surgically treated glioma. Our study offers a new strategy in targeted cancer theranostics through combining the merits of living cells and nanoparticle carriers.

Imaging tracking of the migration of cell-based drug delivery systems are needed for expanding their clinical application for glioma. Here they report inflammation activatable engineered neutrophils containing doxorubicin-loaded magnetic mesoporous silica nanoparticles to image and actively target brain tumors after resection.

Neutrophil-mediated delivery of pixantrone-loaded liposomes decorated with poly(sialic acid)-octadecylamine conjugate for lung cancer treatment

Poly(sialic acid) (PSA) is a natural hydrophilic biodegradable and non-immunogenic biopolymer, receptors for its monomer are expressed on peripheral blood neutrophils (PBNs), which plays important roles in the progression and invasion of tumors. A poly(sialic acid)-octadecylamine conjugate (PSA-ODA) was synthesized and then anchor it on the surface of liposomal pixantrone (Pix-PSL), to achieve an improved anticancer effect. The liposomes were prepared using a remote loading method via a pH gradient, and then assessed for particle size, zeta potential encapsulation efficiency, in vitro release, and in vitro cytotoxicity. Simultaneously, in vitro and in vivo cellular uptake studies confirmed that PSA-decorated liposomes provided an enhanced accumulation of liposomes in PBNs. An in vivo study presented that the anti-tumor activity of Pix-PSL was superior to that of other Pix formulations, probably due to the efficient targeting of PBNs by Pix-PSL, after which PBN containing Pix-PSL (Pix-PSL/PBNs) in the blood circulation are recruited by the tumor microenvironment. These findings suggest that PSA-decorated liposomal Pix may provide a neutrophil-mediated drug delivery system (DDS) for the eradication of tumors, which represents a promising approach for the tumor targeting of chemotherapeutic treatments.

Microglia induces Gas1 expression in human brain tumor-initiating cells to reduce tumorigenecity

We reported previously that microglia decreased the growth of human brain tumor-initiating cells (BTICs). Through microarray analyses of BTICs exposed in vitro to microglia, we found the induction of several genes ascribed to have roles in cell cycle arrest, reduced cell proliferation and differentiation. Herein, we tested the hypothesis that one of these genes, growth arrest specific 1 (Gas1), is a novel growth reduction factor that is induced in BTICs by microglia. We found that microglia increased the expression of Gas1 transcript and protein in glioblastoma patient-derived BTIC lines. Using neurosphere assay we show that RNAi-induced reduction of Gas1 expression in BTICs blunted the microglia-mediated BTIC growth reduction. The role of Gas1 in mediating BTIC growth arrest was further validated using orthotopic brain xenografts in mice. When microglia-induced Gas1-expressing BTIC cells (mGas1-BTICs) were implanted intra-cranially in mice, tumor growth was markedly decreased; this was mirrored in the remarkable increase in survival of mGas1-BT025 and mGas1-BT048 implanted mice, compared to mice implanted with non-microglia-exposed BTIC cells. In conclusion, this study has identified Gas1 as a novel factor and mechanism through which microglia arrest the growth of BTICs for anti-tumor property.

Chronic lymphocytic leukemia cells increase neutrophils survival and promote their differentiation into CD16high CD62Ldim immunosuppressive subset

Reprogramming of neutrophils by malignant cells is well-described for many types of solid tumors, but data remain scarce for hematological diseases. Chronic lymphocytic leukemia (CLL) is characterized for a deep immune dysregulation mediated by leukemic cells that compromises patient's outcome. Murine models of CLL highlight the relevance of myeloid cells as tumor-driven reprogramming targets. In our study, we evaluated neutrophil reprogramming by CLL cells. We first show that the proportion of the CD16^high CD62L^dim neutrophil subset in peripheral blood of CLL patients is increased compared to age-matched healthy donors (HD). In vitro, neutrophils from HD cultured in the presence of CLL cells or conditioned media (CM) from CLL cells exhibited a longer lifespan. Depletion of G-CSF and GM-CSF from CM partially reversed the protective effect. In addition, the proportion of viable neutrophils that displayed a CD16^high CD62L^dim phenotype was increased in the presence of CM from CLL cells, being TGF-β/IL-10 responsible for this effect. Altogether, our results describe a novel mechanism through which CLL cells can manipulate neutrophils.

Cxcr1 mediates recruitment of neutrophils and supports proliferation of tumor-initiating astrocytes in vivo

Neutrophils are first-responders to sites of infection and tissue damage including the inflamed tumor microenvironment. Increasing evidence suggests that crosstalk between tumors and neutrophils can affect the progression of established tumors. However, there is a gap in our understanding of the early events that lead to neutrophil recruitment to oncogene-transformed cells and how these pathways alter tumor progression. Here, we use optically transparent zebrafish larvae to probe the early signals that mediate neutrophil recruitment to Kras-transformed astrocytes. We show that zebrafish larvae with impaired neutrophil function exhibit reduced proliferation of transformed astrocytes supporting a critical role for tumor-associated neutrophils in the early progression of tumorigenesis. Moreover, using mutants and pharmacological inhibition, we show that the chemokine receptor Cxcr1 promotes neutrophil recruitment, proliferation of tumor-initiating cells, and neoplastic mass formation. These findings highlight the power of the larval zebrafish system to image and probe early events in the tumor-initiating microenvironment and demonstrate the potential for neutrophil recruitment signaling pathways such as Cxcl8-Cxcr1 as targets for anti-cancer therapies.

Effects of tumor grade and dexamethasone on myeloid cells in patients with glioma

Efforts to reduce immunosuppression in the solid tumor microenvironment by blocking the recruitment or polarization of tumor associated macrophages (TAM), or myeloid derived suppressor cells (MDSCs), have gained momentum in recent years. Expanding our knowledge of the immune cell types, cytokines, or recruitment factors that are associated with high-grade disease, both within the tumor and in circulation, is critical to identifying novel targets for immunotherapy. Furthermore, a better understanding of how therapeutic regimens, such as Dexamethasone (Dex), chemotherapy, and radiation, impact these factors will facilitate the design of therapies that can be targeted to the appropriate populations and retain efficacy when administered in combination with standard of care regimens. Here we perform quantitative analysis of tissue microarrays made of samples taken from grades I-III astrocytoma and glioblastoma (GBM, grade IV astrocytoma) to evaluate infiltration of myeloid markers CD163, CD68, CD33, and S100A9. Serum, flow cytometric, and Nanostring analysis allowed us to further elucidate the impact of Dex treatment on systemic biomarkers, circulating cells, and functional markers within tumor tissue. We found that common myeloid markers were elevated in Dex-treated grade I astrocytoma and GBM compared to non-neoplastic brain tissue and grade II-III astrocytomas. Cell frequencies in these samples differed significantly from those in Dex-naïve patients in a pattern that depended on tumor grade. In contrast, observed changes in serum chemokines or circulating monocytes were independent of disease state and were due to Dex treatment alone. Furthermore, these changes seen in blood were often not reflected within the tumor tissue.

Conclusions: Our findings highlight the importance of considering perioperative treatment as well as disease grade when assessing novel therapeutic targets or biomarkers of disease.

Preoperative Changes in Hematological Markers and Predictors of Glioma Grade and Survival

Background: Preoperative hematological markers that indicate nutritional, coagulation, and inflammation statuses have prognostic value for gliomas. This study aimed to investigate hematological markers with regard to tumor grades, isocitrate dehydrogenase mutations (IDH), age, and sex in patients with gliomas. Methods: From 2008 to 2017, patients with a pathological diagnosis of glioma who underwent surgery were retrospectively enrolled in this study. Information from clinical records, including age, sex, preoperative experiment tests (routine blood tests, biochemistry, and coagulation examinations), pathological results, and IDH status, was collected. A univariable survival analysis was performed. Hematological factors such as the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte-ratio (PLR), and albumin-to-globulin (AGR) were calculated. The prognostic nutrition index (PNI) was calculated as 10 × serum albumin value (g/dl) + 0.005 × peripheral lymphocyte count (per mm³). Results: Our study included 706 patients. The univariate analysis showed that age, IDH-1, and hematological factors were all significantly associated with overall survival (OS) in patients with gliomas. Our results showed that inflammation markers (NLR, PLR, and fibrinogen) were positively associated with age, whereas AGR was negatively associated with age. The PLR was significantly increased, whereas the AGR and PNI were decreased in women with gliomas, as compared with men. We found that inflammation markers increased and nutrition markers decreased with gliomas grade. However, these hematological markers did not significantly differ with IDH status. NLR was the best single hematological marker for distinguishing glioblastoma (GBM) [0.684 (0.645-0.723)], IDH-wt GBM [0.672 (0.631-0.71)] from other gliomas subtypes. Combinations of age with PNI and age with AGR were the best predictors of GBM [0.750 (0.713-0.786)] and IDH-wt GBM [0.759 (0.719-0.798)], respectively. Conclusion: Preoperative hematological marker levels vary among glioma grades and have high predictive values for GBM.

Cancer Inflammation and Cytokines

Chronic inflammation is a well-recognized tumor-enabling capability, which allows nascent tumors to escape immunosurveillance. A number of soluble and cellular inflammatory mediators take part in the various phases of cancer initiation and progression, giving rise to a fatal conspiracy, which is difficult to efficiently overcome. Tumor-associated macrophages (TAMs) are pivotal players of the tumor microenvironment and, because of their characteristic plasticity, can acquire a number of distinct phenotypes and contribute in different ways to the various phases of cancerogenesis. Tumor-associated neutrophils (TANs) are also emerging as important components of the tumor microenvironment, given their unexpected heterogeneity and plasticity. TAMs and TANs are both integrated in cancer-related inflammation and an ever better understanding of their functions can be useful to tailor the use of anticancer therapeutic approaches and patient follow-up.