Clinical significance of tumor-associated inflammatory cells in metastatic neuroblastoma

Mechanism of Qingjie Fuzheng Granules in inhibiting colitis associated colorectal cancer by regulating TLR4 and IL-4R mediated macrophage polarization

ETHNOPHARMACOLOGICAL RELEVANCE

Qingjie Fuzheng Granules (QFG), a herbal formula, has been employed as an adjuvant therapy for colitis-associated colorectal cancer (CAC), yet the underlying mechanisms by which QFG operates remain unclear.

AIMS OF THE STUDY

The aim of this study is to investigate whether the potential mechanism of QFG against CAC is associated with macrophage polarization.

MATERIALS AND METHODS

Non-targeted metabolomics and molecular docking assessed potential compounds of QFG to interact with targets associated with macrophage polarization. A model of AOM/DSS-induced CAC mice was established to analyze the effects of QFG on macrophage polarization using flow cytometry and immunohistochemical staining. In vitro experiments involved models of Ana-1 macrophages, either induced by varying QFG concentrations or with MD2 knockdown, to analyze M1-like phenotype. Meanwhile, M2-like macrophages models induced by IL-4 or culture supernatant of CT26 cells were utilized to assess the effects of QFG on M2-like macrophages. Finally, the mRNA expression of M1-like phenotype related to TLR4 pathways and the protein expression in IL-4R-mediated pathways were analyzed using RT-qPCR and Western blot, respectively.

RESULTS

Molecular docking confirmed the presence of binding sites between the ingredients of QFG and IL-4R or TLR4/MD2 receptor complex. QFG could induce a shift in macrophages towards an M1-like phenotype while inhibiting an M2-like phenotype in the colon with CAC mice and Ana-1 macrophages. QFG resulted in the upregulation of iNOS, IL-6, IL-1β, and TNF-α mRNA expression, which could be counteracted by TAK242, SR11302, INH14, PDTC, and LY294002, or by the knockdown of MD2. Meanwhile, QFG inhibited IL-4R-induced phosphorylation of STAT 6 and Akt.

CONCLUSION

Various monomer components within QFG can bind to MD2 or IL-4R, respectively, thereby inducing macrophages towards an M1-like phenotype through TLR4-mediated NF-κB, MAPK, and PI3K/Akt pathway activation, or inhibiting macrophages towards an M2-like phenotype via IL-4R-mediated JAKs pathway inhibition, ultimately exerting an inhibitory effect on the occurrence and development of CAC.

Ex vivo-expanded and activated haploidentical natural killer cells infusion before autologous stem cell transplantation in high-risk neuroblastoma: a phase I/II pilot study

Given that natural killer (NK; CD3 - CD56 +) cells-mediated antibody-dependent cell cytotoxicity (ADCC) plays an important role in targeting neuroblastoma (NB) cells, adoptive cell therapy (ACT) utilizing expanded and activated haploidentical NK cells has emerged as a promising immunotherapeutic approach in pediatric patients with high-risk NB. In this pilot study, five pediatric patients with high-risk NB were enrolled. After harvesting hematopoietic progenitor cells (HPCs), patients received an intravenous infusion of high-activity iodine-131 (131I)-meta-iodobenzylguanidine (131I-MIBG). Seven days after the 131I-MIBG infusion and before the delivery of a single infusion of haploidentical purified NK cells, patients were administered a preparative regimen to establish a lymphodepleted host environment conducive to improved donor NK cell survival. Four days after the NK cell infusion, patients underwent the conditioning regimen, then received autologous hematopoietic stem cell transplantation (AHSCT). All patients achieved successful neutrophil and platelet engraftment. No adverse reactions were noted during or after the infusion of NK cells. Our study shows that incorporating NK cell infusion before AHSCT as a component of the conditioning regimen for consolidative therapy in pediatric patients with high-risk NB can be safe and well tolerated. IRCT Registration Number: IRCT20140818018842N32.

FOXJ3, a novel tumor suppressor in neuroblastoma

Neuroblastoma (NB) poses a significant challenge in pediatric cancer care due to its aggressive nature and poor prognosis. While advances have been made in clinical treatments, therapy resistance remains a tough hurdle in NB treatment. While much research has focused on identifying oncogenes in NB, there has been less emphasis on understanding tumor suppressors. This study aimed to discover a new transcription factor that could address patient stage, risk level, and MYCN amplification status while exhibiting tumor-suppressive properties in NB patients. Using advanced bioinformatics techniques, we identified unique transcription factor signature that corresponded to patient characteristics. By analyzing regulon specificity scores, we prioritized Forkhead Box J3 (FOXJ3) as a potential novel driver transcription factor with tumor-suppressive functions in NB. Validation experiments on NB patients and patient-derived xenograft (PDX) tumors confirmed higher FOXJ3 expression in low-risk versus high-risk patients and in PDXs from diagnostic tumors versus relapse-specific tumors. Notably, the overexpression of FOXJ3 was associated with reduced cell density, proliferation, cells in S phase, colony-formation ability, transwell migration, neurosphere formation, spheroid diameter, and inhibition of AKT signaling in NB cells. Overall, these findings suggest that FOXJ3 functions as a novel tumor suppressor in NB, holding promise for potential therapeutic interventions.

Loss of ARID1A leads to a cold tumor phenotype via suppression of IFNγ signaling

The collapse of inflammatory signaling that recruits cytotoxic immune cells to the tumor microenvironment contributes to the immunologically cold tumor phenotype in neuroblastoma (NB) and is a barrier to NB immunotherapy. Multiple studies have reported that MYCN amplification, a trait of high-risk NB, correlates with a loss of inflammatory signaling; but MYCN also correlates with 1p36 deletions in NB where the SWI/SNF chromatin remodeling complex subunit ARID1A (1p36.11) is located. ARID1A is known to support inflammatory signaling in adult cancers but its role in NB inflammatory signaling is unexplored. We find MYCN overexpression causes a stronger inflammatory response to interferon-gamma (IFNγ). ARID1A knockdown causes a weaker inflammatory response and reduces IFNγ induced gene signatures for the transcription factor interferon response factor 1 (IRF1). We found ARID1A is a functional interactor of IRF1 by co-immunoprecipitation studies, and ARID1A silencing causes loss of activating chromatin marks at the IRF1 target gene CXCL10. We model that IRF1 uses ARID1A containing SWI/SNF to promote CXCL10 in response to IFNγ. Our work clarifies that the loss of ARID1A, which tightly associates with MYCN amplification, causes reduced inflammatory signaling. This work finds that ARID1A is a critical regulator of inflammatory signaling in NB and provides rationale for testing immune therapies in MYCN amplified NB that are effective in adult ARID1A mutated cancers.

EDF1 accelerates ganglioside GD3 accumulation to boost CD52-mediated CD8+ T cell dysfunction in neuroblastoma

BACKGROUND

Heterogeneous clinical features and prognosis in neuroblastoma (NB) children are frequently dominated by immune elements. Dysfunction and apoptosis in immune cells result from the exposure to continuous tumor-related antigen stimulation and coinhibitory signals. To date, key factors pointing to the restriction of NB-specific CD8+ T cells remain elusive.

METHODS

We performed bulk-RNA sequencing and lipidomic analyses of children with mediastinal NB. Bioinformatics analysis and biological validation were applied to uncover the underlying mechanism.

RESULTS

Three subtypes were identified using nonnegative matrix factorization (NMF), among which we highlighted an apoptotic status of infiltrated CD8+ T cells, along with the highest CD52 and EDF1 expression in Cluster3 (C3) subtypes. It was verified that high EDF1 expression in NB cells led to Lactosylceramide (LacCer) accumulation, as well as downstream ganglioside-GD3, which subsequently increased the expression of CD52 and immune checkpoint genes, chemotaxis, and apoptosis-related events in activated CD8+T cells. Mechanistically, EDF1 was recruited as a coactivator to form the NF-κB/RelA/EDF1 complex, which further prevented the promoter region methylation of ST8SIA1, to elevate its transcription.

CONCLUSION

These findings characterize abundant GD3 in NB cells, which regulated by the EDF1/RelA/ST8SIA1 axis, is responsible for CD8+ T cell dysfunction. Inhibition of EDF1 may reduce suppressive factors and prevent immune escape of NB cells. Modulating NB-associated GD3 levels through metabolic intervention is beneficial for tuning the depth and duration of responses to current NB therapies. The integration of transcriptomic and lipidomic data offers a more comprehensive understanding of the interaction between LacCer metabolites and the immune status in NB.

Targeting MYCN upregulates L1CAM tumor antigen in MYCN-dysregulated neuroblastoma to increase CAR T cell efficacy

Current treatment protocols have limited success against MYCN-amplified neuroblastoma. Adoptive T cell therapy presents an innovative strategy to improve cure rates. However, L1CAM-targeting CAR T cells achieved only limited response against refractory/relapsed neuroblastoma so far. We investigated how oncogenic MYCN levels influence tumor cell response to CAR T cells, as one possible factor limiting clinical success. A MYCN-inducible neuroblastoma cell model was created. L1CAM-CAR T cell effector function was assessed (activation markers, cytokine release, tumor cytotoxicity) after coculture with the model or MYCN-amplified neuroblastoma cell lines. RNA sequencing datasets characterizing the model were compared to publicly available RNA/proteomic datasets. MYCN-directed L1CAM regulation was explored using public ChIP-sequencing datasets. Synergism between CAR T cells and the indirect MYCN inhibitor, MLN8237, was assessed in vitro using the Bliss model and in vivo in an immunocompromised mouse model. Inducing high MYCN levels in the neuroblastoma cell model reduced L1CAM expression and, consequently, L1CAM-CAR T cell effector function in vitro. Primary neuroblastomas possessing high MYCN levels expressed lower levels of both the L1CAM transcript and L1CAM tumor antigen. MLN8237 treatment restored L1CAM tumor expression and L1CAM-CAR T cell effector function. Combining MLN8237 and L1CAM-CAR T cell treatment synergistically enhanced MYCN-overexpressing tumor cytotoxicity in vitro and in vivo concomitant with severe in vivo toxicity. We identify target antigen downregulation as source of resistance against L1CAM-CAR T cells in MYCN-driven neuroblastoma cells. These data suggest that L1CAM-CAR T cell therapy combined with pharmacological MYCN inhibition may benefit patients with MYCN-amplified neuroblastoma.

Natural killer cell-based therapies in neuroblastoma

Neuroblastoma (NB) is the most common extracranial solid tumor of childhood forming around 15 % of all pediatric tumors. Despite advances in the treatment of NB, high-risk patients still face a grave prognosis. Adoptive cell therapies based on NK cells are becoming an assistive treatment for such cases. Moreover, there is also evidence that NKT-based therapies have promising results in the management of NB. Lower complications in comparison with adoptive T cell therapies, various cell sources, and miscellaneous tumor recognition mechanisms are some of the advantages of NK- and NKT-based therapies. This review is dedicated to searching for recent advances in this field.

Identification of novel markers for neuroblastoma immunoclustering using machine learning

Background

Due to the unique heterogeneity of neuroblastoma, its treatment and prognosis are closely related to the biological behavior of the tumor. However, the effect of the tumor immune microenvironment on neuroblastoma needs to be investigated, and there is a lack of biomarkers to reflect the condition of the tumor immune microenvironment.

Methods

The GEO Database was used to download transcriptome data (both training dataset and test dataset) on neuroblastoma. Immunity scores were calculated for each sample using ssGSEA, and hierarchical clustering was used to categorize the samples into high and low immunity groups. Subsequently, the differences in clinicopathological characteristics and treatment between the different groups were examined. Three machine learning algorithms (LASSO, SVM-RFE, and Random Forest) were used to screen biomarkers and synthesize their function in neuroblastoma.

Results

In the training set, there were 362 samples in the immunity_L group and 136 samples in the immunity_H group, with differences in age, MYCN status, etc. Additionally, the tumor microenvironment can also affect the therapeutic response of neuroblastoma. Six characteristic genes (BATF, CXCR3, GIMAP5, GPR18, ISG20, and IGHM) were identified by machine learning, and these genes are associated with multiple immune-related pathways and immune cells in neuroblastoma.

Conclusions

BATF, CXCR3, GIMAP5, GPR18, ISG20, and IGHM may serve as biomarkers that reflect the conditions of the immune microenvironment of neuroblastoma and hold promise in guiding neuroblastoma treatment.

Three-dimensional silk fibroin scaffolded co-culture of human neuroblastoma and innate immune cells

Neuroblastoma (NB) is the most common pediatric extracranial solid tumor. It accounts for 50 % of cancers diagnosed in infants less than 1 year old, and 10 % of all pediatric cancer deaths in the United States. High-risk patients have a less than 50 % 5-year survival rate with current treatment strategies. The complex tumor microenvironment of NB makes the development of treatment strategies for high-risk patients challenging. There is increasing evidence that intratumoral immune suppression plays an important role in the progression and invasion of NB tumors. Few three-dimensional (3D) cancer models include components of the innate immune system. This work develops a preclinical 3D NB-immune co-culture model using SK-N-AS NB cells, NK-92 natural killer cells, and THP-1 derived macrophages, co-cultured on porous 3D silk scaffolds to provide tumor architecture. Conditioned media and indirect co-culturing showed changes in SK-N-AS gene expression associated with immunoregulatory signaling, and changes in NK-92 gene expression that are associated with reduced cytotoxicity. This motivated the development of a 3D direct co-culture system in which NB cells were seeded prior to immune cells to allow incorporation and deposition of extracellular matrix within the construct. Immune cells were then incorporated into the model to achieve direct co-culture with SK-N-AS cells. Changes in THP-1 macrophage polarization toward a more M2-like phenotype were observed in 3D direct co-culture, as well as altered NK-92 cell protein secretion and cytotoxic activity. Preliminary testing of immunotherapeutics within the model was conducted on both NB-macrophage and NB-NK co-cultures, but the model demonstrated limited response to immunotherapeutics. This work lays the foundation for building high-throughput therapeutic screening models for the improved treatment NB and other solid tumors.

Molecular profiling of core immune-escape genes highlights TNFAIP3 as an immune-related prognostic biomarker in neuroblastoma

BACKGROUND

Neuroblastoma (NB) is the most prevalent and deadliest pediatric solid tumor. With of over 50% of high-risk neuroblastoma cases relapse, the imperative for novel drug targets and therapeutic strategies is accentuated. In neuroblastoma, the existence of tumor-associated macrophages (TAMs) correlates with an unfavorable patient prognosis. However, the clinical relevance and prognostic implications of regulatory genes linked to TAMs infiltration in neuroblastoma remain unclear, and further study is required.

METHODS

We conducted a comprehensive analysis utilizing transcriptome expression profiles from three primary datasets associated with neuroblastoma (GSE45547, GSE49710, TARGET) to identify hub genes implicated in immune evasion within neuroblastoma. Subsequently, we utilized single-cell RNA sequencing analysis on 17 clinical neuroblastoma samples to investigate the expression and distribution of these hub genes, leading to the identification of TNFAIP3. The above three public databases were merged to allowed for the validation of TNFAIP3's molecular functions through GO and KEGG analysis. Furthermore, we assessed TNFAIP3's correlation with immune infiltration and its potential immunotherapeutic impact by multiple algorithms. Our single-cell transcriptome data revealed the role of TNFAIP3 in macrophage polarization. Finally, preliminary experimental verifications to confirm the biological functions of TNFAIP3-mediated TAMs in NB.

RESULTS

A total of 6 genes related to immune evasion were screened and we found that TNFAIP3 exhibited notably higher expression in macrophages than other immune cell types, based on the scRNA-sequencing data. GO and KEGG analysis showed that low expression of TNFAIP3 significantly correlated with the activation of multiple oncogenic pathways as well as immune-related pathways. Then validation affirmed that individuals within the TNFAIP3 high-expression cohort could potentially derive greater advantages from immunotherapeutic interventions, alongside exhibiting heightened immune responsiveness. Deciphering the pseudotime trajectory of macrophages, we revealed the potential of TNFAIP3 in inducing the polarization of macrophages towards the M1 phenotype. Finally, we confirmed that patients in the TNFAIP3 high expression group might benefit more from immunotherapy or chemotherapy as substantiated by RT-qPCR and immunofluorescence examinations. Moreover, the role of TNFAIP3 in macrophage polarization was validated. Preliminary experiment showed that TNFAIP3-mediated TAMs inhibit the proliferation, migration and invasion capabilities of NB cells.

CONCLUSIONS

Our results suggest that TNFAIP3 was first identified as a promising biomarker for immunotherapy and potential molecular target in NB. Besides, the presence of TNFAIP3 within TAMs may offer a novel therapeutic strategy for NB.

Current Knowledge and Perspectives of Immunotherapies for Neuroblastoma

Neuroblastoma (NBL) cells highly express disialoganglioside GD2, which is restricted and weakly expressed in selected healthy cells, making it a desirable target of immunotherapy. Over the past two decades, application of dinutuximab, an anti-GD2 monoclonal antibody (mAb), has been one of the few new therapies to substantially improve outcomes to current levels. Given the persistent challenge of relapse and therapeutic resistance, there is an urgent need for new effective and tolerable treatment options for high-risk NBL. Recent breakthroughs in immune checkpoint inhibitor (ICI) therapeutics have not translated into high-risk NBL, like many other major pediatric solid tumors. Given the suppressed tumor microenvironment (TME), single ICIs like anti-CTLA4 and anti-PD1 have not demonstrated significant antitumor response rates. Meanwhile, emerging studies are reporting novel advancements in GD2-based therapies, targeted therapies, nanomedicines, and other immunotherapies such as adoptive transfer of natural killer (NK) cells and chimeric antigen receptors (CARs), and these hold interesting promise for the future of high-risk NBL patient care. Herein, we summarize the current state of the art in NBL therapeutic options and highlight the unique challenges posed by NBL that have limited the successful adoption of immune-modifying therapies. Through this review, we aim to direct the field's attention to opportunities that may benefit from a combination immunotherapy strategy.

Nuclear factor-κB activation by transforming growth factor-β1 drives tumour microenvironment-mediated drug resistance in neuroblastoma

BACKGROUND

Intrinsic and extrinsic factors in the tumour microenvironment (TME) contribute to therapeutic resistance. Here we demonstrate that transforming growth factor (TGF)-β1 produced in the TME increased drug resistance of neuroblastoma (NB) cells.

METHODS

Human NB cell lines were tested in vitro for their sensitivity to Doxorubicin (DOX) and Etoposide (ETOP) in the presence of tumour-associated macrophages (TAM) and mesenchymal stromal cells/cancer-associated fibroblasts (MSC/CAF). These experiments were validated in xenotransplanted and primary tumour samples.

RESULTS

Drug resistance was associated with an increased expression of efflux transporter and anti-apoptotic proteins. Upregulation was dependent on activation of nuclear factor (NF)-κB by TGF-β-activated kinase (TAK1) and SMAD2. Resistance was reversed upon pharmacologic and genetic inhibitions of NF-κB, and TAK1/SMAD2. Interleukin-6, leukaemia inhibitory factor and oncostatin M were upregulated by this TGF-β/TAK1/NF-κB/SMAD2 signalling pathway contributing to drug resistance via an autocrine loop activating STAT3. An analysis of xenotransplanted NB tumours revealed an increased presence of phospho (p)-NF-κB in tumours co-injected with MSC/CAF and TAM, and these tumours failed to respond to Etoposide but responded if treated with a TGF-βR1/ALK5 inhibitor. Nuclear p-NF-κB was increased in patient-derived tumours rich in TME cells.

CONCLUSIONS

The data provides a novel insight into a targetable mechanism of environment-mediated drug resistance.

The miR-29 family facilitates the activation of NK-cell immune responses by targeting the B7-H3 immune checkpoint in neuroblastoma

Neuroblastoma (NB) is a highly aggressive pediatric cancer that originates from immature nerve cells, presenting significant treatment challenges due to therapy resistance. Despite intensive treatment, approximately 50% of high-risk NB cases exhibit therapy resistance or experience relapse, resulting in poor outcomes often associated with tumor immune evasion. B7-H3 is an immune checkpoint protein known to inhibit immune responses. MicroRNAs (miRNAs) are small non-coding RNAs involved in post-transcriptional gene regulation. Our study aims to explore the impact of miRNAs on B7-H3 regulation, the anti-tumor immune response, and tumorigenicity in NB. Analysis of NB patients and patient-derived xenograft tumors revealed a correlation between higher B7-H3 expression and poorer patient survival. Notably, deceased patients exhibited a depletion of miR-29 family members (miR-29a, miR-29b, and miR-29c), which displayed an inverse association with B7-H3 expression in NB patients. Overexpression and knockdown experiments demonstrated that these miRNAs degrade B7-H3 mRNA, resulting in enhanced NK cell activation and cytotoxicity. In vivo, experiments provided further evidence that miR-29 family members reduce tumorigenicity, macrophage infiltration, and microvessel density, promote infiltration and activation of NK cells, and induce tumor cell apoptosis. These findings offer a rationale for developing more effective combination treatments that leverage miRNAs to target B7-H3 in NB patients.

Immune Microenvironment in Childhood Cancers: Characteristics and Therapeutic Challenges

The tumor immune microenvironment is pivotal in cancer initiation, advancement, and regulation. Its molecular and cellular composition is critical throughout the disease, as it can influence the balance between suppressive and cytotoxic immune responses within the tumor's vicinity. Studies on the tumor immune microenvironment have enriched our understanding of the intricate interplay between tumors and their immunological surroundings in various human cancers. These studies illuminate the role of significant components of the immune microenvironment, which have not been extensively explored in pediatric tumors before and may influence the responsiveness or resistance to therapeutic agents. Our deepening understanding of the pediatric tumor immune microenvironment is helping to overcome challenges related to the effectiveness of existing therapeutic strategies, including immunotherapies. Although in the early stages, targeted therapies that modulate the tumor immune microenvironment of pediatric solid tumors hold promise for improved outcomes. Focusing on various aspects of tumor immune biology in pediatric patients presents a therapeutic opportunity that could improve treatment outcomes. This review offers a comprehensive examination of recent literature concerning profiling the immune microenvironment in various pediatric tumors. It seeks to condense research findings on characterizing the immune microenvironment in pediatric tumors and its impact on tumor development, metastasis, and response to therapeutic modalities. It covers the immune microenvironment's role in tumor development, interactions with tumor cells, and its impact on the tumor's response to immunotherapy. The review also discusses challenges targeting the immune microenvironment for pediatric cancer therapies.

The Neuroblastoma Microenvironment, Heterogeneity and Immunotherapeutic Approaches

Neuroblastoma is a peripheral nervous system tumor that almost exclusively occurs in young children. Although intensified treatment modalities have led to increased patient survival, the prognosis for patients with high-risk disease is still around 50%, signifying neuroblastoma as a leading cause of cancer-related deaths in children. Neuroblastoma is an embryonal tumor and is shaped by its origin from cells within the neural crest. Hence, neuroblastoma usually presents with a low mutational burden and is, in the majority of cases, driven by epigenetically deregulated transcription networks. The recent development of Omic techniques has given us detailed knowledge of neuroblastoma evolution, heterogeneity, and plasticity, as well as intra- and intercellular molecular communication networks within the neuroblastoma microenvironment. Here, we discuss the potential of these recent discoveries with emphasis on new treatment modalities, including immunotherapies which hold promise for better future treatment regimens.

Opaganib Downregulates N-Myc Expression and Suppresses In Vitro and In Vivo Growth of Neuroblastoma Cells

Neuroblastoma (NB), the most common cancer in infants and the most common solid tumor outside the brain in children, grows aggressively and responds poorly to current therapies. We have identified a new drug (opaganib, also known as ABC294640) that modulates sphingolipid metabolism by inhibiting the synthesis of sphingosine 1-phosphate (S1P) by sphingosine kinase-2 and elevating dihydroceramides by inhibition of dihydroceramide desaturase. The present studies sought to determine the potential therapeutic activity of opaganib in cell culture and xenograft models of NB. Cytotoxicity assays demonstrated that NB cells, including cells with amplified MYCN, are effectively killed by opaganib concentrations well below those that accumulate in tumors in vivo. Opaganib was shown to cause dose-dependent decreases in S1P and hexosylceramide levels in Neuro-2a cells, while concurrently elevating levels of dihydroceramides. As with other tumor cells, opaganib reduced c-Myc and Mcl-1 protein levels in Neuro-2a cells, and also reduced the expression of the N-Myc protein. The in vivo growth of xenografts of human SK-N-(BE)2 cells with amplified MYCN was suppressed by oral administration of opaganib at doses that are well tolerated in mice. Combining opaganib with temozolomide plus irinotecan, considered the backbone for therapy of relapsed or refractory NB, resulted in increased antitumor activity in vivo compared with temozolomide plus irinotecan or opaganib alone. Mice did not lose additional weight when opaganib was combined with temozolomide plus irinotecan, indicating that the combination is well tolerated. Opaganib has additive antitumor activity toward Neuro-2a tumors when combined with the checkpoint inhibitor anti-CTLA-4 antibody; however, the combination of opaganib with anti-PD-1 or anti-PD-L1 antibodies did not provide increased antitumor activity over that seen with opaganib alone. Overall, the data demonstrate that opaganib modulates sphingolipid metabolism and intracellular signaling in NB cells and inhibits NB tumor growth alone and in combination with other anticancer drugs. Amplified MYCN does not confer resistance to opaganib, and, in fact, the drug attenuates the expression of both c-Myc and N-Myc. The safety of opaganib has been established in clinical trials with adults with advanced cancer or severe COVID-19, and so opaganib has excellent potential for treating patients with NB, particularly in combination with temozolomide and irinotecan or anti-CTLA-4 antibody.

Pediatric Solid Cancers: Dissecting the Tumor Microenvironment to Improve the Results of Clinical Immunotherapy

Despite advances in their diagnosis and treatment, pediatric cancers remain among the leading causes of death in childhood. The development of immunotherapies and other forms of targeted therapies has significantly changed the prognosis of some previously incurable cancers in the adult population. However, so far, the results in pediatric cohorts are disappointing, which is mainly due to differences in tumor biology, including extreme heterogeneity and a generally low tumor mutational burden. A central role in the limited efficacy of immunotherapeutic approaches is played by the peculiar characteristics of the tumor microenvironment (TME) in pediatric cancer, with the scarcity of tumor infiltration by T cells and the abundance of stromal cells endowed with lymphocyte suppressor and tumor-growth-promoting activity. Thus, progress in the treatment of pediatric solid tumors will likely be influenced by the ability to modify the TME while delivering novel, more effective therapeutic agents. In this review, we will describe the TME composition in pediatric solid tumors and illustrate recent advances in treatment for the modulation of immune cells belonging to the TME.

Contribution of plasma MicroRNA-21, MicroRNA-155 and circulating monocytes plasticity to childhood neuroblastoma development and induction treatment outcome

Neuroblastoma (NB) accounts for 15% of all pediatric cancer fatalities (NB). Biomarkers that facilitate early NB detection are needed because by the time of diagnosis, over half of NBs had spread. MicroRNA-21(miR-21) and miR-155 are involved in cancer biology due to their immune modulation functions. Altered monocyte subset distribution is thought to be involved in a number of solid tumors due to its immunological role. We aimed to investigate the expression levels of miR-21 and miR-155 and their association with circulating monocytes subsets in NB and to evaluate if they correlate to the disease pathogenesis and outcome.

PATIENTS AND METHODS

This case control study involved 79 children classified into 39 newly diagnosed NB children and 40 age and sex matched healthy children. Real-time PCR was used to assess the expression of plasma miR-21 and miR-155. The frequency of circulating monocytes subsets was assessed by flow cytometry.

RESULTS

NB group showed significant up-regulation in expression of miR-21(20.9 folds) and miR-155 (1.8 folds) when compared to the control group (p < 0.001) and (p = 0.02) respectively. Also, frequency of circulating intermediate monocytes revealed significant up regulation in children with NB. In NB patients, there was a positive correlation between miR-21 and frequency of total and intermediate monocytes (r = 0.5 p < 0.001 and r = 0.7, p < 0.001, respectively). We found no discernible differences when we compared study markers between the high risk and intermediate risk groups. In addition, no significant difference was seen in study markers when patients were sub-grouped according to their induction treatment response. ROC curve analysis revealed that miR-21 up-regulation distinguished NB in childhood at an AUC of 0.94 (82% sensitivity and 100% specificity) while miR-155 up-regulation had less capacity to distinguish NB in childhood at an AUC of 0.65 (38% sensitivity and 93% specificity).

CONCLUSION

miR-21 can be utilized as a sensitive biomarker for childhood NB development. In pediatric NB, miR-21 was linked to intermediate monocyte plasticity. Both, miR-21 and miR-155 had no impact on NB outcome.

Impact of the peripheral blood inflammatory indices and modified nomogram-revised risk index on survival of Extranodal Nasal-Type Natural Killer/T-Cell lymphoma

BACKGROUND

At present, peripheral blood markers are easily accessible information and clinically valuable prognostic indicators in extranodal nasal-type natural killer/T-cell lymphoma (ENKTCL). Nevertheless, the role of its comprehensive score in ENKTCL remains to be determined.

OBJECTIVE

Therefore, this study aimed to investigate the prognostic effect of the peripheral inflammation score on ENKTCL.

METHODS

The retrospective study included 183 patients with ENKTCL. Univariate Cox regression analyses and least absolute shrinkage and selection operator (LASSO) Cox regression were used to construct the inflammation-related prognostic index named Risk. Univariate and multivariate Cox regression analyses and regression adjustment with propensity score matching (PSM) were used to evaluate the prognostic ability of risk. The performance of the modified nomogram-revised risk index (NRI) by integrating risk was evaluated with the area under the time-dependent receiver operating characteristic (ROC) curve (AUC), decision curve analysis (DCA), and integrated Brier score (IBS).

RESULTS

The risk cut-off value, constructed by the lymphocyte count, platelet count, albumin level, LMR, and PNI, was -1.3486. Before PSM, multivariate analysis showed that risk was significantly associated with OS (HR = 2.577, 95% CI = 1.614-4.114, P< 0.001) and PFS (HR = 2.679, 95% CI = 1.744-4.114, P< 0.001). After PSM adjustment, risk was still an independent factor for OS (HR = 2.829, 95% CI = 1.601-5.001, P< 0.001) and PFS (HR = 2.877, 95% CI = 1.735-4.770, P< 0.001). With the NRI, the modified NRI by integrating risk increased the AUC and clinical net benefit and decreased the IBS.

CONCLUSIONS

Risk is an easily accessible and inexpensive indicator that may be used as a prognostic marker and could improve NRI predictive power in patients with ENKTCL.

Targeting the myeloid microenvironment in neuroblastoma

Myeloid cells (granulocytes and monocytes/macrophages) play an important role in neuroblastoma. By inducing a complex immunosuppressive network, myeloid cells pose a challenge for the adaptive immune system to eliminate tumor cells, especially in high-risk neuroblastoma. This review first summarizes the pro- and anti-tumorigenic functions of myeloid cells, including granulocytes, monocytes, macrophages, and myeloid-derived suppressor cells (MDSC) during the development and progression of neuroblastoma. Secondly, we discuss how myeloid cells are engaged in the current treatment regimen and explore novel strategies to target these cells in neuroblastoma. These strategies include: (1) engaging myeloid cells as effector cells, (2) ablating myeloid cells or blocking the recruitment of myeloid cells to the tumor microenvironment and (3) reprogramming myeloid cells. Here we describe that despite their immunosuppressive traits, tumor-associated myeloid cells can still be engaged as effector cells, which is clear in anti-GD2 immunotherapy. However, their full potential is not yet reached, and myeloid cell engagement can be enhanced, for example by targeting the CD47/SIRPα axis. Though depletion of myeloid cells or blocking myeloid cell infiltration has been proven effective, this strategy also depletes possible effector cells for immunotherapy from the tumor microenvironment. Therefore, reprogramming of suppressive myeloid cells might be the optimal strategy, which reverses immunosuppressive traits, preserves myeloid cells as effectors of immunotherapy, and subsequently reactivates tumor-infiltrating T cells.

A novel endoplasmic reticulum stress-related lncRNA signature for prognosis prediction and immune response evaluation in Stomach adenocarcinoma

BACKGROUND

Stomach adenocarcinoma (STAD) is a significant contributor to cancer-related mortality worldwide. Although previous research has identified endoplasmic reticulum stress (ERS) as a regulator of various tumor-promoting properties of cancer cells, the impact of ERS-related long non-coding RNAs (lncRNAs) on STAD prognosis has not yet been investigated. Therefore, our study aims to develop and validate an ERS-related lncRNA signature that can accurately predict the prognosis of STAD patients.

METHODS

We collected RNA expression profiles and clinical data of STAD patients from The Cancer Genome Atlas (TCGA) and identified ERS-related genes from the Molecular Signature Database (MSigDB). Co-expression analysis enabled us to identify ERS-related lncRNAs, and we applied univariate Cox, least absolute shrinkage, and selection operator (LASSO), and multivariate Cox regression analyses to construct a predictive signature comprising of 9 ERS-related lncRNAs. We assessed the prognostic accuracy of our signature using Kaplan-Meier survival analysis, and validated our predictive signature in an independent gene expression omnibus (GEO) cohort. We also performed tumor mutational burden (TMB) and tumor immune microenvironment (TIME) analyses. Enrichment analysis was used to investigate the functions and biological processes of the signature, and we identified two distinct STAD patient subgroups through consensus clustering. Finally, we performed drug sensitivity analysis and immunologic efficacy analysis to explore further insights.

RESULTS

The 9 ERS related-lncRNAs signature demonstrated satisfactory predictive performance as an independent prognostic marker and was significantly associated with STAD clinicopathological characteristics. Furthermore, patients in the high-risk group displayed a worse STAD prognosis than those in the low-risk group. Notably, gene set enrichment analysis (GSEA) revealed significant enrichment of extracellular matrix pathways in the high-risk group, indicating their involvement in STAD progression. Additionally, the high-risk group exhibited significantly lower TMB expression levels than the low-risk group. Consensus clustering revealed two distinct STAD patient subgroups, with Cluster 1 exhibiting higher immune cell infiltration and more active immune functions. Drug sensitivity analysis suggested that the low-risk group was more responsive to oxaliplatin, epirubicinl, and other drugs.

CONCLUSION

Our study highlights the crucial regulatory roles of ERS-related lncRNAs in STAD, with significant clinical implications. The 9-lncRNA signature we have constructed represents a reliable prognostic indicator that has the potential to inform more personalized treatment decisions for STAD patients. These findings shed new light on the pathogenesis of STAD and its underlying molecular mechanisms, offering opportunities for novel therapeutic strategies to be developed for STAD patients.

Neuroblastoma: an ongoing cold front for cancer immunotherapy

Neuroblastoma is the most frequent extracranial childhood tumour but effective treatment with current immunotherapies is challenging due to its immunosuppressive microenvironment. Efforts to date have focused on using immunotherapy to increase tumour immunogenicity and enhance anticancer immune responses, including anti-GD2 antibodies; immune checkpoint inhibitors; drugs which enhance macrophage and natural killer T (NKT) cell function; modulation of the cyclic GMP-AMP synthase-stimulator of interferon genes pathway; and engineering neuroblastoma-targeting chimeric-antigen receptor-T cells. Some of these strategies have strong preclinical foundation and are being tested clinically, although none have demonstrated notable success in treating paediatric neuroblastoma to date. Recently, approaches to overcome heterogeneity of neuroblastoma tumours and treatment resistance are being explored. These include rational combination strategies with the aim of achieving synergy, such as dual targeting of GD2 and tumour-associated macrophages or natural killer cells; GD2 and the B7-H3 immune checkpoint; GD2 and enhancer of zeste-2 methyltransferase inhibitors. Such combination strategies provide opportunities to overcome primary resistance to and maximize the benefits of immunotherapy in neuroblastoma.

Anti-CCL2 antibody combined with etoposide prolongs survival in a minimal residual disease mouse model of neuroblastoma

C-C motif chemokine ligand 2 (CCL2) is a monocyte chemoattractant that promotes metastatic disease and portends a poor prognosis in many cancers. To determine the potential of anti-CCL2 inhibition as a therapy for recurrent metastatic disease in neuroblastoma, a mouse model of minimal residual disease was utilized in which residual disease was treated with anti-CCL2 monoclonal antibody with etoposide. The effect of anti-CCL2 antibody on neuroblastoma cells was determined in vitro with cell proliferation, transwell migration, and 2-dimensional chemotaxis migration assays. The in vivo efficacy of anti-CCL2 antibody and etoposide against neuroblastoma was assessed following resection of primary tumors formed by two cell lines or a patient-derived xenograft (PDX) in immunodeficient NOD-scid gamma mice. In vitro, anti-CCL2 antibody did not affect cell proliferation but significantly inhibited neuroblastoma cell and monocyte migration towards an increasing CCL2 concentration gradient. Treatment of mice with anti-CCL2 antibody combined with etoposide significantly increased survival of mice after resection of primary tumors, compared to untreated mice.

Targeting of intracellular oncoproteins with peptide-centric CARs

The majority of oncogenic drivers are intracellular proteins, constraining their immunotherapeutic targeting to mutated peptides (neoantigens) presented by individual human leukocyte antigen (HLA) allotypes1. However, most cancers have a modest mutational burden that is insufficient for generating responses using neoantigen-based therapies2,3. Neuroblastoma is a paediatric cancer that harbours few mutations and is instead driven by epigenetically deregulated transcriptional networks4. Here we show that the neuroblastoma immunopeptidome is enriched with peptides derived from proteins essential for tumorigenesis. We focused on targeting the unmutated peptide QYNPIRTTF discovered on HLA-A*24:02, which is derived from the neuroblastoma-dependency gene and master transcriptional regulator PHOX2B. To target QYNPIRTTF, we developed peptide-centric chimeric antigen receptors (PC-CARs) through a counter panning strategy using predicted potentially cross-reactive peptides. We further proposed that PC-CARs can recognize peptides on additional HLA allotypes when presenting a similar overall molecular surface. Informed by our computational modelling results, we show that PHOX2B PC-CARs also recognize QYNPIRTTF presented by HLA-A*23:01, the most common non-A2 allele in people with African ancestry. Finally, we demonstrate potent and specific killing of neuroblastoma cells expressing these HLAs in vitro and complete tumour regression in mice. These data suggest that PC-CARs have the potential to expand the pool of immunotherapeutic targets to include non-immunogenic intracellular oncoproteins and allow targeting through additional HLA allotypes in a clinical setting.

Irreversible repolarization of tumour-associated macrophages by low-Pi stress inhibits the progression of hepatocellular carcinoma

Numerous studies have shown the positive correlation between high levels of Pi and tumour progression. A critical goal of macrophage-based cancer therapeutics is to reduce anti-inflammatory macrophages (M2) and increase proinflammatory antitumour macrophages (M1). This study aimed to investigate the relationship between macrophage polarization and low-Pi stress. First, the spatial populations of M2 and M1 macrophages in 22 HCC patient specimens were quantified and correlated with the local Pi concentration. The levels of M2 and M1 macrophage markers expressed in the peritumour area were higher than the intratumour levels, and the expression of M2 markers was positively correlated with Pi concentration. Next, monocytes differentiated from THP-1 cells were polarized against different Pi concentrations to investigate the activation or silencing of the expression of p65, IκB-α and STAT3 as well as their phosphorylation. Results showed that low-Pi stress irreversibly repolarizes tumour-associated macrophages (TAMs) towards the M1 phenotype by silencing stat6 and activating p65. Moreover, HepG-2 and SMCC-7721 cells were cultured in conditioned medium to investigate the innate anticancer immune effects on tumour progression. Both cancer cell lines showed reduced proliferation, migration and invasion, as epithelial-mesenchymal transition (EMT) was inactivated. In vivo therapeutic effect on the innate and adaptive immune processes was validated in a subcutaneous liver cancer model by the intratumoural injection of sevelamer. Tumour growth was significantly inhibited by the partial deprivation of intratumoural Pi as the tumour microenvironment under low-Pi stress is more immunostimulatory. The anticancer immune response, activated by low-Pi stress, suggests a new macrophage-based immunotherapeutic modality.

A Multi-Color Flow Cytometric Assay for Quantifying Dinutuximab Binding to Neuroblastoma Cells in Tumor, Bone Marrow, and Blood

GD2, a disialoganglioside, is present on the surface of most neuroblastomas, as well as on some other cancers, such as melanoma and osteogenic sarcoma. The anti-GD2 antibody ch14.18 (dinutuximab) has an FDA-registered indication for use as maintenance therapy for high-risk neuroblastoma with cytokines and 13-cis-retinoic acid after myeloablative therapy. Recent studies using immunohistochemistry of tumor or tumor cells in marrow have shown that some neuroblastomas are negative for GD2. Dinutuximab and other anti-GD2 antibodies are increasingly used in combination with cytotoxic chemotherapy for treating relapsed neuroblastoma, so it is important to be able to identify patients with tumor cells with low GD2 expression, as such patients may experience toxicity but not benefit from the antibody therapy. As the most common clinical samples available for relapsed neuroblastoma are bone marrow aspirates, we developed a method to quantify dinutuximab binding density and the frequency of neuroblastoma cells positive for the antibody in bone marrow aspirates. Here, we describe a multi-color flow cytometry assay that employs non-GD2 antibodies to identify neuroblastoma cells in a mixed population (tumor, bone marrow, or blood) and an anti-GD2 antibody to quantify both the frequency and density of GD2 expression on neuroblastoma cells.

Targeting long noncoding RNAs in neuroblastoma: Progress and prospects

Neuroblastoma (NB) is the third most prevalent tumor that mostly influences infants and young children. Although different treatments have been developed for the treatment of NB, high-risk patients have been reported to have low survival rates. Currently, long noncoding RNAs (lncRNAs) have shown an attractive potential in cancer research and a party of investigations have been performed to understand mechanisms underlying tumor development through lncRNA dysregulation. Researchers have just newly initiated to exhibit the involvement of lncRNAs in NB pathogenesis. In this review article, we tried to clarify the point we stand with respect to the involvement of lncRNAs in NB. Moreover, implications for the pathologic roles of lncRNAs in the development of NB have been discussed. It seems that some of these lncRNAs have promising potential to be applied as biomarkers for NB prognosis and treatment.

An updated overview of the application of CAR-T cell therapy in neurological diseases

Genetically modified immune cells, especially CAR-T cells, have captured the attention of scientists over the past 10 years. In the fight against cancer, these cells have a special place. Treatment for hematological cancers, autoimmune disorders, and cancers must include CAR-T cell therapy. Determining the therapeutic targets, side effects, and use of CAR-T cells in neurological disorders, including cancer and neurodegenerative diseases, is the goal of this study. Due to advancements in genetic engineering, CAR-T cells have become crucial in treating some neurological disorders. CAR-T cells have demonstrated a positive role in treating neurological cancers like Glioblastoma and Neuroblastoma due to their ability to cross the blood-brain barrier and use diverse targets. However, CAR-T cell therapy for MS diseases is being researched and could be a potential treatment option. This study aimed to access the most recent studies and scientific articles in the field of CAR-T cells in neurological diseases and/or disorders.

Development and validation of a 21-gene prognostic signature in neuroblastoma

Survival outcomes for patients with neuroblastoma vary markedly and reliable prognostic markers and risk stratification tools are lacking. We sought to identify and validate a transcriptomic signature capable of predicting risk of mortality in patients with neuroblastoma. The TARGET NBL dataset (n = 243) was used to develop the model and two independent cohorts, E-MTAB-179 (n = 478) and GSE85047 (n = 240) were used as validation sets. EFS was the primary outcome and OS was the secondary outcome of interest for all analysis. We identified a 21-gene signature capable of stratifying neuroblastoma patients into high and low risk groups in the E-MTAB-179 (HR 5.87 [3.83-9.01], p < 0.0001, 5 year AUC 0.827) and GSE85047 (HR 3.74 [2.36-5.92], p < 0.0001, 5 year AUC 0.815) validation cohorts. Moreover, the signature remained independent of known clinicopathological variables, and remained prognostic within clinically important subgroups. Further, the signature was effectively incorporated into a risk model with clinicopathological variables to improve prognostic performance across validation cohorts (Pooled Validation HR 6.93 [4.89-9.83], p < 0.0001, 5 year AUC 0.839). Similar prognostic utility was also demonstrated with OS. The identified signature is a robust independent predictor of EFS and OS outcomes in neuroblastoma patients and can be combined with clinically utilized clinicopathological variables to improve prognostic performance.

Tuftsin-tailored fusion protein inhibits the growth of circulating gastric tumor cells associated with macrophage phagocytosis

Circulating tumor cells (CTCs) are a major cause of tumor metastasis and resistance to anticancer therapies. To date, no effective low-toxicity chemotherapeutic agents or antibodies have exhibited significant clinical activity against CTCs. Macrophages are important mediators of antitumor immunity. Tuftsin (TF), a tetrapeptide located at residues 289-292 of the CH2 domain of the Fc region of the IgG heavy chain, binds to Nrp-1, a receptor on the surface of macrophages that promotes phagocytosis and induces nonspecific activation of the immune system against tumors. Lidamycin (LDM) is an antitumor chemotherapy agent that is strongly cytotoxic to tumors and can dissociate into an apoprotein (LDP) and active enediyne (AE) in vitro. We previously constructed the fusion protein LDP-TF through genetic engineering and inserted the chromophore AE to produce LDM-TF, which can target macrophages to promote their phagocytic and cytotoxic activity against tumor cells. Preliminary experiments confirmed the anti-tumor activity of LDM-TFs. In this study, we found that LDM-TF effectively inhibited the growth of CTCs of gastric cancer origin and enhanced macrophage phagocytosis both in vivo and in vitro. Tumor cell expression of CD47, which helps to evade phagocytosis by macrophages, was substantially downregulated by LDM-TF. Notably, our in vitro experiments demonstrated that the combination of LDM-TF and anti-CD47 antibodies promoted phagocytosis more than either component alone. Our findings demonstrate the significant inhibitory effect of LDM-TF on the growth of CTCs of gastric cancer origin and suggest that the combination of LDM-TF and anti-CD47 antibodies may exhibit synergistic effects, thereby providing a new option for the clinical treatment of patients with advanced tumors that have metastasized.

Single-cell transcriptomics and epigenomics unravel the role of monocytes in neuroblastoma bone marrow metastasis

Metastasis is the major cause of cancer-related deaths. Neuroblastoma (NB), a childhood tumor has been molecularly defined at the primary cancer site, however, the bone marrow (BM) as the metastatic niche of NB is poorly characterized. Here we perform single-cell transcriptomic and epigenomic profiling of BM aspirates from 11 subjects spanning three major NB subtypes and compare these to five age-matched and metastasis-free BM, followed by in-depth single cell analyses of tissue diversity and cell-cell interactions, as well as functional validation. We show that cellular plasticity of NB tumor cells is conserved upon metastasis and tumor cell type composition is NB subtype-dependent. NB cells signal to the BM microenvironment, rewiring via macrophage mgration inhibitory factor and midkine signaling specifically monocytes, which exhibit M1 and M2 features, are marked by activation of pro- and anti-inflammatory programs, and express tumor-promoting factors, reminiscent of tumor-associated macrophages. The interactions and pathways characterized in our study provide the basis for therapeutic approaches that target tumor-to-microenvironment interactions.

Targeted immune activation in pediatric solid tumors: opportunities to complement local control approaches

Surgery or radiation therapy is nearly universally applied for pediatric solid tumors. In many cases, in diverse tumor types, distant metastatic disease is present and evades surgery or radiation. The systemic host response to these local control modalities may lead to a suppression of antitumor immunity, with potential negative impact on the clinical outcomes for patients in this scenario. Emerging evidence suggests that the perioperative immune responses to surgery or radiation can be modulated therapeutically to preserve anti-tumor immunity, with the added benefit of preventing these local control approaches from serving as pro-tumorigenic stimuli. To realize the potential benefit of therapeutic modulation of the systemic response to surgery or radiation on distant disease that evades these modalities, a detailed knowledge of the tumor-specific immunology as well as the immune responses to surgery and radiation is imperative. In this Review we highlight the current understanding of the tumor immune microenvironment for the most common peripheral pediatric solid tumors, the immune responses to surgery and radiation, and current evidence that supports the potential use of immune activating agents in the perioperative window. Finally, we define existing knowledge gaps that limit the current translational potential of modulating perioperative immunity to achieve effective anti-tumor outcomes.

Reversible transitions between noradrenergic and mesenchymal tumor identities define cell plasticity in neuroblastoma

Noradrenergic and mesenchymal identities have been characterized in neuroblastoma cell lines according to their epigenetic landscapes and core regulatory circuitries. However, their relationship and relative contribution in patient tumors remain poorly defined. We now document spontaneous and reversible plasticity between the two identities, associated with epigenetic reprogramming, in several neuroblastoma models. Interestingly, xenografts with cells from each identity eventually harbor a noradrenergic phenotype suggesting that the microenvironment provides a powerful pressure towards this phenotype. Accordingly, such a noradrenergic cell identity is systematically observed in single-cell RNA-seq of 18 tumor biopsies and 15 PDX models. Yet, a subpopulation of these noradrenergic tumor cells presents with mesenchymal features that are shared with plasticity models, indicating that the plasticity described in these models has relevance in neuroblastoma patients. This work therefore emphasizes that intrinsic plasticity properties of neuroblastoma cells are dependent upon external cues of the environment to drive cell identity.

Monocyte and Macrophage in Neuroblastoma: Blocking Their Pro-Tumoral Functions and Strengthening Their Crosstalk with Natural Killer Cells

Over the past decade, immunotherapy has represented an enormous step forward in the fight against cancer. Immunotherapeutic approaches have increasingly become a fundamental part of the combined therapies currently adopted in the treatment of patients with high-risk (HR) neuroblastoma (NB). An increasing number of studies focus on the understanding of the immune landscape in NB and, since this tumor expresses low or null levels of MHC class I, on the development of new strategies aimed at enhancing innate immunity, especially Natural Killer (NK) cells and macrophages. There is growing evidence that, within the NB tumor microenvironment (TME), tumor-associated macrophages (TAMs), which mainly present an M2-like phenotype, have a crucial role in mediating NB development and immune evasion, and they have been correlated to poor clinical outcomes. Importantly, TAM can also impair the antibody-dependent cellular cytotoxicity (ADCC) mediated by NK cells upon the administration of anti-GD2 monoclonal antibodies (mAbs), the current standard immunotherapy for HR-NB patients. This review deals with the main mechanisms regulating the crosstalk among NB cells and TAMs or other cellular components of the TME, which support tumor development and induce drug resistance. Furthermore, we will address the most recent strategies aimed at limiting the number of pro-tumoral macrophages within the TME, reprogramming the TAMs functional state, thus enhancing NK cell functions. We also prospectively discuss new or unexplored aspects of human macrophage heterogeneity.

Interaction between tumor cell TNFR2 and monocyte membrane-bound TNF-α triggers tumorigenic inflammation in neuroblastoma

BACKGROUND

Tumor progression and resistance to therapy in children with neuroblastoma (NB), a common childhood cancer, are often associated with infiltration of monocytes and macrophages that produce inflammatory cytokines. However, the mechanism by which tumor-supportive inflammation is initiated and propagated remains unknown. Here, we describe a novel protumorigenic circuit between NB cells and monocytes that is triggered and sustained by tumor necrosis factor alpha (TNF-α).

METHODS

We used NB knockouts (KOs) of TNF-α and TNFRSF1A mRNA (TNFR1)/TNFRSF1B mRNA (TNFR2) and TNF-α protease inbitor (TAPI), a drug that modulates TNF-α isoform expression, to assess the role of each component in monocyte-associated protumorigenic inflammation. Additionally, we employed NB-monocyte cocultures and treated these with clinical-grade etanercept, an Fc-TNFR2 fusion protein, to neutralize signaling by both membrane-bound (m) and soluble (s)TNF-α isoforms. Further, we treated NOD/SCID/IL2Rγ(null) mice carrying subcutaneous NB/human monocyte xenografts with etanercept and evaluated the impact on tumor growth and angiogenesis. Gene set enrichment analysis (GSEA) was used to determine whether TNF-α signaling correlates with clinical outcomes in patients with NB.

RESULTS

We found that NB expression of TNFR2 and monocyte membrane-bound tumor necrosis factor alpha is required for monocyte activation and interleukin (IL)-6 production, while NB TNFR1 and monocyte soluble TNF-α are required for NB nuclear factor kappa B subunit 1 (NF-κB) activation. Treatment of NB-monocyte cocultures with clinical-grade etanercept completely abrogated release of IL-6, granulocyte colony-stimulating factor (G-CSF), IL-1α, and IL-1β and eliminated monocyte-induced enhancement of NB cell proliferation in vitro. Furthermore, etanercept treatment inhibited tumor growth, ablated tumor angiogenesis, and suppressed oncogenic signaling in mice with subcutaneous NB/human monocyte xenografts. Finally, GSEA revealed significant enrichment for TNF-α signaling in patients with NB that relapsed.

CONCLUSIONS

We have described a novel mechanism of tumor-promoting inflammation in NB that is strongly associated with patient outcome and could be targeted with therapy.

Macrophage infiltration promotes regrowth in MYCN-amplified neuroblastoma after chemotherapy

Despite aggressive treatment, the 5-year event-free survival rate for children with high-risk neuroblastoma is <50%. While most high-risk neuroblastoma patients initially respond to treatment, often with complete clinical remission, many eventually relapse with therapy-resistant tumors. Novel therapeutic alternatives that prevent the recurrence of therapy-resistant tumors are urgently needed. To understand the adaptation of neuroblastoma under therapy, we analyzed the transcriptomic landscape in 46 clinical tumor samples collected before (PRE) or after (POST) treatment from 22 neuroblastoma patients. RNA sequencing revealed that many of the top-upregulated biological processes in POST MYCN amplified (MNA⁺) tumors compared to PRE MNA⁺ tumors were immune-related, and there was a significant increase in numerous genes associated with macrophages. The infiltration of macrophages was corroborated by immunohistochemistry and spatial digital protein profiling. Moreover, POST MNA⁺ tumor cells were more immunogenic compared to PRE MNA⁺ tumor cells. To find support for the macrophage-induced outgrowth of certain subpopulations of immunogenic tumor cells following treatment, we examined the genetic landscape in multiple clinical PRE and POST tumor samples from nine neuroblastoma patients revealing a significant correlation between an increased amount of copy number aberrations (CNA) and macrophage infiltration in POST MNA⁺ tumor samples. Using an in vivo neuroblastoma patient-derived xenograft (PDX) chemotherapy model, we further show that inhibition of macrophage recruitment with anti-CSF1R treatment prevents the regrowth of MNA⁺ tumors following chemotherapy. Taken together, our work supports a therapeutic strategy for fighting the relapse of MNA⁺ neuroblastoma by targeting the immune microenvironment.

Neuroblastoma Tumor-Associated Mesenchymal Stromal Cells Regulate the Cytolytic Functions of NK Cells

Neuroblastoma tumor-associated mesenchymal stromal cells (NB-TA-MSC) have been extensively characterized for their pro-tumorigenic properties, while their immunosuppressive potential, especially against NK cells, has not been thoroughly investigated. Herein, we study the immune-regulatory potential of six primary young and senescent NB-TA-MSC on NK cell function. Young cells display a phenotype (CD105+/CD90+/CD73+/CD29+/CD146+) typical of MSC cells and, in addition, express high levels of immunomodulatory molecules (MHC-I, PDL-1 and PDL-2 and transcriptional-co-activator WWTR1), able to hinder NK cell activity. Notably, four of them express the neuroblastoma marker GD2, the most common target for NB immunotherapy. From a functional point of view, young NB-TA-MSC, contrary to the senescent ones, are resistant to activated NK cell-mediated lysis, but this behavior is overcome using anti-CD105 antibody TRC105 that activates antibody-dependent cell-mediated cytotoxicity. In addition, proliferating NB-TA-MSC, but not the senescent ones, after six days of co-culture, inhibit proliferation, expression of activating receptors and cytolytic activity of freshly isolated NK. Inhibitors of the soluble immunosuppressive factors L-kynurenine and prostaglandin E2 efficiently counteract this latter effect. Our data highlight the presence of phenotypically heterogeneous NB-TA-MSC displaying potent immunoregulatory properties towards NK cells, whose inhibition could be mandatory to improve the antitumor efficacy of targeted immunotherapy.

Outcomes Following GD2-Directed Postconsolidation Therapy for Neuroblastoma After Cessation of Random Assignment on ANBL0032: A Report From the Children's Oncology Group

PURPOSE

Postconsolidation immunotherapy including dinutuximab, granulocyte-macrophage colony-stimulating factor, and interleukin-2 improved outcomes for patients with high-risk neuroblastoma enrolled on the randomized portion of Children's Oncology Group study ANBL0032. After random assignment ended, all patients were assigned to immunotherapy. Survival and toxicities were assessed.

PATIENTS AND METHODS

Patients with a pre-autologous stem cell transplant (ASCT) response (excluding bone marrow) of partial response or better were eligible. Demographics, stage, tumor biology, pre-ASCT response, and adverse events were summarized using descriptive statistics. Event-free survival (EFS) and overall survival (OS) from time of enrollment (up to day +200 from last ASCT) were evaluated.

RESULTS

From 2009 to 2015, 1,183 patients were treated. Five-year EFS and OS for the entire cohort were 61.1 ± 1.9% and 71.9 ± 1.7%, respectively. For patients ≥ 18 months old at diagnosis with International Neuroblastoma Staging System stage 4 disease (n = 662) 5-year EFS and OS were 57.0 ± 2.4% and 70.9 ± 2.2%, respectively. EFS was superior for patients with complete response/very good partial response pre-ASCT compared with those with PR (5-year EFS: 64.2 ± 2.2% v 55.4 ± 3.2%, P = .0133); however, OS was not significantly different. Allergic reactions, capillary leak, fever, and hypotension were more frequent during interleukin-2-containing cycles than granulocyte-macrophage colony-stimulating factor-containing cycles (P < .0001). EFS was superior in patients with higher peak dinutuximab levels during cycle 1 (P = .034) and those with a high affinity FCGR3A genotype (P = .0418). Human antichimeric antibody status did not correlate with survival.

CONCLUSION

Analysis of a cohort assigned to immunotherapy after cessation of random assignment on ANBL0032 confirmed previously described survival and toxicity outcomes. EFS was highest among patients with end-induction complete response/very good partial response. Among patients with available data, higher dinutuximab levels and FCGR3A genotype were associated with superior EFS. These may be predictive biomarkers for dinutuximab therapy.

Fibroblasts and macrophages cooperate to create a pro-tumorigenic and immune resistant environment via activation of TGF-β/IL-6 pathway in neuroblastoma

Tumor-associated macrophages (TAM) and cancer-associated fibroblasts (CAF) and their precursor mesenchymal stromal cells (MSC) are often detected together in tumors, but how they cooperate is not well understood. Here, we show that TAM and CAF are the most abundant nonmalignant cells and are present together in untreated human neuroblastoma (NB) tumors that are also poorly infiltrated with T and natural killer (NK) cells. We then show that MSC and CAF-MSC harvested from NB tumors protected human monocytes (MN) from spontaneous apoptosis in an interleukin (IL)-6 dependent mechanism. The interactions of MN and MSC with NB cells resulted in a significant induction or increase in the expression of several pro-tumorigenic cytokines/chemokines (TGF-β1, MCP-1, IL-6, IL-8, and IL-4) but not of anti-tumorigenic cytokines (TNF-α, IL-12) by MN or MSC, while also inducing cytokine expression in quiescent NB cells. We then identified a TGF-β1/IL-6 pathway where TGF-β1 stimulated the expression of IL-6 in NB cells and MSC, promoting TAM survival. Evidence for the contribution of TAM and MSC to the activation of this pathway was then provided in xenotransplanted NB tumors and patients with primary tumors by demonstrating a direct correlation between the presence of CAF and p-SMAD2 and p-STAT3. The data highlight a new mechanism of interaction between TAM and CAF supporting their pro-tumorigenic function in cancer.

Prediction to the prognosis of children with neuroblastoma by nomogram based on the first-diagnosed inflammatory markers

BACKGROUND

Patients with high-risk neuroblastoma (NB) have a poor prognosis. The prognostic significance of inflammatory biomarker-based nomograms for children with NB has not been previously studied.

METHODS

Part of patients diagnosed with NB in our center from January 2016 to March 2022 were included in the study. Inflammatory biomarkers were primary outcome measures, including C-reactive protein (CRP), ferritin, neutrophil to lymphocyte ratio (NLR), and lymphocyte to monocyte ratio (LMR), platelet to lymphocyte ratio (PLR) and systemic immune-inflammation index (SII). Univariate and multivariate survival analyses were performed to assess the prognostic value of these indicators for overall survival (OS) in NB children, showing the Kaplan-Meier survival curves and plotting the nomogram. C-index were used to detect predictability.

RESULTS

93 NB patients were retrospectively analyzed. CRP, ferritin, NLR, PLR, and SII were significantly associated with OS of NB patients, while LMR were found to be not predictive of OS for NB patients. The established nomogram is well-calibrated, and the C-index is 0.731.

CONCLUSION

Survival analysis found part of inflammatory biomarkers related to the prognosis of NB. The nomogram could be used as a convenient predictive tool in clinical practice to evaluate the prognosis of NB children at first diagnosis.

Expression of programmed cell death-1 on neuroblastoma cells in TH-MYCN transgenic mice

BACKGROUND

Immunotherapy may improve the poor prognosis of high-risk neuroblastoma. Programmed cell death-1 (PD-1) is expressed in several cancers. The tyrosine hydroxylase MYCN (TH-MYCN) transgenic mouse model is widely used in neuroblastoma research, but detailed information on its immunological background is lacking. Therefore, we studied the immunological tumor microenvironment and tumor cell surface antigen expression in homozygote and hemizygote mice and effects of antibody therapy against PD-1.

METHODS

CD4, CD8, CD11b, and CD11c expression in immune cells from retroperitoneal lymph nodes and spleen was analyzed by flow cytometry. Tumor cell surface antigen expression was confirmed, and data from homozygote and hemizygote mice were compared. Effects of anti-PD-1 antibody were evaluated.

RESULTS

CD4-, CD8-, CD11b-, and CD11c-positive cells were not significantly different in homozygote and hemizygote mice, and CD11b- and CD11c-positive cells were identified in the tumor microenvironment in both. Tumor cells expressed PD-1, and anti-PD-1 antibody had anti-tumor effects and significantly reduced the percentage of living tumor cells in cultures after 2 h.

CONCLUSION

The immunological background is similar in homozygote and hemizygote TH-MYCN transgenic mice, and both have PD-1-positive tumor cells. Anti-PD-1 antibody suppresses tumor growth. This mouse model may be a useful for studying immunotherapy of neuroblastoma.

GDPD5 Related to Lipid Metabolism Is a Potential Prognostic Biomarker in Neuroblastoma

Neuroblastoma (NB) is an extracranial solid tumor in children with poor prognosis in high-risk patients and its pathogenesis and prognostic markers urgently need to be explored. This study aimed to explore potential biomarkers related to NB from the aspect of lipid metabolism. Fifty-eight lipid metabolism-related differentially expressed genes between high-risk NB and non-high-risk NB in the GSE49710 dataset were analyzed using bioinformatics, including 45 down-regulated genes and 13 up-regulated genes. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis identified steroid hormone biosynthesis as an abnormal metabolic pathway in high-risk NB. Survival analysis established a three-gene prognostic model, including ACHE, GDPD5 and PIK3R1. In the test data, the AUCs of the established prognostic models used to predict patient survival at 1, 3 and 5 years were 0.84, 0.90 and 0.91, respectively. Finally, in the SH-SY5Y cell line, it was verified that overexpression of GDPD5 can inhibit cell proliferation and migration, as well as affect the lipid metabolism of SH-SY5Y, but not the sugar metabolism. hsa-miR-592 was predicted to be a potential target miRNA of GDPD5 by bioinformatics. In conclusion, this study develops a lipid-metabolism-related gene-based prognostic model for NB and demonstrates that GDPD5 inhibits SH-SY5Y proliferation and migration and may be targeted by hsa-miR-592 and inhibit SH-SY5Y fat synthesis.

Opsoclonus-myoclonus syndrome associated with neuroblastoma: Insights into antitumor immunity

Opsoclonus-myoclonus syndrome (OMS) is a rare neurological disorder. Half of these cases occur in children with neuroblastoma. Neuroblastoma patients with OMS usually have better oncological outcomes than those without OMS even after stratification by tumor stage and age, indicating that factors mediating OMS may also inhibit tumor cell proliferation. Although the mechanisms underlying OMS remain undefined, the cytokines and lymphocytes alterations in the cerebrospinal fluid support the concept that it is a pattern of neuroinflammation due to an autoimmune effect. The presence of lymphoid follicles consisting of follicular dendritic cells, CD20⁺ B lymphocytes, CD3⁺ T lymphocytes, and CD68⁺ macrophages in the tumor microenvironment in OMS-associated neuroblastoma support the autoimmune nature of this disorder. This review focuses on the clinical and genetic features of OMS-associated neuroblastoma, and we update readers on immune features of neuroblastoma with or without OMS to gain insights into antitumor immunity as it relates to tumor biology and prognosis.

Identification of hub genes and their correlation with infiltration of immune cells in MYCN positive neuroblastoma based on WGCNA and LASSO algorithm

Background

The prognosis of MYCN positive NB is poor, and there is no targeted drug for N-myc at present. This study aims to screen out hub genes closely related to MYCN, analyze the relationship between hub genes and NB microenvironment, and provide basis for molecular targeted therapy of MYCN positive NB.

Methods

We combined the microarray data of GSE45547 (n=649) and GSE49710 (n=498), screened the DEGs between MYCN positive (n=185) and MYCN negative NB (n=951), performed WGCNA, Lasso regression and Roc analyses on the merged matrix, and obtained the hub genes related to MYCN in the training group. We performed ssGSEA on the experimental group to calculate the infiltration level of 28 kinds of immune cells in each sample, compared the differences of immune cell infiltration between MYCN positive and MYCN negative group. The influences of hub genes on the distribution of each immune cell were also analyzed by ssGSEA. The expression differences of the three hub genes were verified in the E-MTAB-8248 cohort (n=223), and the correlation between hub genes and prognosis of NB was calculated by Kaplan-Meier method in GSE62564 (n=498) and the validation group. We also verified the expression differences of hub genes by qRT-PCR in SK-N-BE(2), SKNDZ, Kelly and SH-SY5Y cell lines.

Results

Here were 880 DEGs including 420 upregulated and 460 downregulated genes in MYCN positive NB in the training group. Overlap of the DEGs and WGCNA networks identified four shared genes, namely, ZNF695, CHEK1, C15ORF42 and EXO1, as candidate hub genes in MYCN positive NB. Three core genes, ZNF695, CHEK1 and C15ORF42, were finally identified by Lasso regression and Roc analyses. ZNF695, CHEK1 and C15ORF42 were highly expressed in MYCN positive NB tissues and cell lines. These three genes were closely related to the prognosis of children with NB. Except that Activated CD4 T cell and Type2 T helper cell increased, the infiltration levels of the other 26 cells decreased significantly in MYCN positive NB tissues. The infiltration levels of Type2 T helper cell and Activated CD4 T cell were also significantly positively correlated with the expression levels of the three hub genes.

Conclusion

ZNF695, CHEK1 and C15ORF42 are highly expressed in MYCN positive NB, and their expression levels are negatively correlated with the prognosis of children with NB. The infiltration levels of Activated CD4 T cell and Type2 T helper cell increased in the microenvironment of MYCN positive NB and were significantly positively correlated with the expression levels of the three hub genes. The results of this study provide that ZNF695, CHEK1 and C15ORF42 may be potential prognostic markers and immunotherapy targets for MYCN positive NB.

Mesenchymal and adrenergic cell lineage states in neuroblastoma possess distinct immunogenic phenotypes

Apart from the anti-GD2 antibody, immunotherapy for neuroblastoma has had limited success due to immune evasion mechanisms, coupled with an incomplete understanding of predictors of response. Here, from bulk and single-cell transcriptomic analyses, we identify a subset of neuroblastomas enriched for transcripts associated with immune activation and inhibition and show that these are predominantly characterized by gene expression signatures of the mesenchymal lineage state. By contrast, tumors expressing adrenergic lineage signatures are less immunogenic. The inherent presence or induction of the mesenchymal state through transcriptional reprogramming or therapy resistance is accompanied by innate and adaptive immune gene activation through epigenetic remodeling. Mesenchymal lineage cells promote T cell infiltration by secreting inflammatory cytokines, are efficiently targeted by cytotoxic T and natural killer cells and respond to immune checkpoint blockade. Together, we demonstrate that distinct immunogenic phenotypes define the divergent lineage states of neuroblastoma and highlight the immunogenic potential of the mesenchymal lineage.

Tumoral heterogeneity in neuroblastoma

Neuroblastoma is a solid, neuroendocrine tumor with divergent clinical behavior ranging from asymptomatic to fatal. The diverse clinical presentations of neuroblastoma are directly linked to the high intra- and inter-tumoral heterogeneity it presents. This heterogeneity is strongly associated with therapeutic resistance and continuous relapses, often leading to fatal outcomes. The development of successful risk assessment and tailored treatment strategies lies in evaluating the extent of heterogeneity via the accurate genetic and epigenetic profiling of distinct cell subpopulations present in the tumor. Recent studies have focused on understanding the molecular mechanisms that drive tumoral heterogeneity in pursuing better therapeutic and diagnostic approaches. This review describes the cellular, genetic, and epigenetic aspects of neuroblastoma heterogeneity. In addition, we summarize the recent findings on three crucial factors that can lead to heterogeneity in solid tumors: the inherent diversity of the progenitor cells, the presence of cancer stem cells, and the influence of the tumor microenvironment.

CAMTA1 gene affects the ischemia-reperfusion injury by regulating CCND1

Epigenetic modulations lead to changes in gene expression, including DNA methylation, histone modifications, and noncoding RNAs. In recent years, epigenetic modifications have been related to the pathogenesis of different types of cancer, cardiovascular disease, and other diseases. Emerging evidence indicates that DNA methylation could be associated with ischemic stroke (IS) and plays a role in pathological progression, but the underlying mechanism has not yet been fully understood. In this study, we used human methylation 850K BeadChip to analyze the differences in gene methylation status in the peripheral blood samples from two groups (3 IS patients vs. 3 healthy controls). According to their bioinformatics profiling, we found 278 genes with significantly different methylation levels. Seven genes with the most significant methylation modifications were validated in two expanded groups (100 IS patients vs. 100 healthy controls). The CAMTA1 gene had significantly different methylation changes in patients compared to the controls. To understand the CAMTA1 function in stroke, we generated CAMTA1 knockout in SH-SY5Y cells. RNA seq results in CAMTA1 knockout cells revealed the pathways and gene set enrichments involved in cellular proliferation and cell cycle. Furthermore, a series of experiments demonstrated that in the oxygen-glucose deprivation/re-oxygenation (OGD/R) model system, the expression of cyclin D1, an essential regulator of cell cycle progression, was increased in SH-SY5Y CAMTA1 KO cells. Increasing evidence demonstrated that ischemic stress could inappropriately raise cyclin D1 levels in mature neurons. However, the molecular signals leading to an increased cyclin D1 level are unclear. Our findings demonstrate for the first time that the CAMTA1 gene could regulate cyclin D1 expression and implicate their role in strokes.