Immunotherapy approaches targeting neuroblastoma

Neuroblastoma-A Review of Combination Immunotherapy

Neuroblastoma is the most common extracranial solid tumor found in childhood and is responsible for 15% of deaths among children with cancer. Although multimodal therapies focused on surgery, chemotherapy, radiotherapy, and stem cell transplants have favorable results in many cases, the use of conventional therapies has probably reached the limit their possibility. Almost half of the patients with neuroblastoma belong to the high-risk group. Patients in this group require a combination of several therapeutic approaches. It has been shown that various immunotherapies combined with conventional methods can work synergistically. Due to the development of such therapeutic methods, we present combinations and forms of combining immunotherapy, focusing on their mechanisms and benefits but also their limitations and potential side effects.

Narrative review: precision medicine applications in neuroblastoma-current status and future prospects

Background and Objective

Neuroblastoma (NB) is a common malignant tumor in children, and its treatment remains challenging. Precision medicine, as an individualized treatment strategy, aims to improve efficacy and reduce toxicity by combining unique patient- and tumor-related factors, bringing new hope for NB treatment. In this article, we review the evidence related to precision medicine in NB, with a focus on potential clinically actionable targets and a series of targeted drugs associated with NB.

Methods

We conducted an extensive search in PubMed, EMBASE, and Web of Science using key terms and database-specific strategies, filtered for time and language, to ensure a comprehensive collection of literature related to precision medicine in NB. The main search terms consisted of "neuroblastoma", "precision medicine", "pediatrics", and "targeting". The articles included in this study encompass those published from 1985 to the present, without restrictions on the type of articles.

Key Content and Findings

ALK inhibitors and MYCN inhibitors have been developed to interfere with tumor cell growth and dissemination, thereby improving treatment outcomes. Additionally, systematic testing to identify relevant driver mutations is crucial and can be used for diagnosis and prognostic assessment through the detection of many associated molecular markers. Furthermore, liquid biopsy, a non-invasive tumor detection method, can complement tissue biopsy and play a role in NB by analyzing circulating tumor DNA and circulating tumor cells to provide genetic information and molecular characteristics of the tumor. Recently, trials conducted by many pediatric oncology groups have shown the urgent need for new approaches to cure relapsed and refractory patients.

Conclusions

The purpose of this review is to summarize the latest advances in clinical treatment of NB, to better understand and focus on the development of promising treatment approaches, and to expedite the transition to the precision medicine clinical relevance in NB patients.

A spatial cell atlas of neuroblastoma reveals developmental, epigenetic and spatial axis of tumor heterogeneity

Neuroblastoma is a pediatric cancer arising from the developing sympathoadrenal lineage with complex inter- and intra-tumoral heterogeneity. To chart this complexity, we generated a comprehensive cell atlas of 55 neuroblastoma patient tumors, collected from two pediatric cancer institutions, spanning a range of clinical, genetic, and histologic features. Our atlas combines single-cell/nucleus RNA-seq (sc/scRNA-seq), bulk RNA-seq, whole exome sequencing, DNA methylation profiling, spatial transcriptomics, and two spatial proteomic methods. Sc/snRNA-seq revealed three malignant cell states with features of sympathoadrenal lineage development. All of the neuroblastomas had malignant cells that resembled sympathoblasts and the more differentiated adrenergic cells. A subset of tumors had malignant cells in a mesenchymal cell state with molecular features of Schwann cell precursors. DNA methylation profiles defined four groupings of patients, which differ in the degree of malignant cell heterogeneity and clinical outcomes. Using spatial proteomics, we found that neuroblastomas are spatially compartmentalized, with malignant tumor cells sequestered away from immune cells. Finally, we identify spatially restricted signaling patterns in immune cells from spatial transcriptomics. To facilitate the visualization and analysis of our atlas as a resource for further research in neuroblastoma, single cell, and spatial-omics, all data are shared through the Human Tumor Atlas Network Data Commons at www.humantumoratlas.org.

Enhancing the sensitization of neuroblastoma to radiotherapy by the construction of a dual-channel parallel free radicals nanoamplifier

Radiation therapy (RT) has emerged as one of the most promising anti-tumor strategies for neuroblastoma. Nevertheless, the special tumor microenvironment (TME), including hypoxic and GSH-overexpressed TME, often greatly restricts the RT outcome. In this study, we demonstrated a dual-channel parallel radicals nanoamplifier (ATO@PAE-PEG-AS1411/Fe3+). The nanoamplifier was shaped into a bilayer shell-core structure, in which atovaquone-loaded poly (β-amino esters)-poly (ethylene glycol) (ATO@PAE-PEG) served as the core while Fe3+-absorbed AS1411 aptamer (AS1411/Fe3+) served as the shell. Taking advantage of the targeting ability of AS1411, ATO@PAE-PEG-AS1411/Fe3+ specifically accumulated in tumor cells, and then released ATO as well as Fe3+ in response to the acidic TME. The released ATO dramatically inhibited the mitochondrial respiration of tumor cells, thus sparing vast amounts of oxygen for the generation of free radicals during RT process, which was the first free radicals-amplifying pathway Meanwhile, the released Fe3+ could consume the tumor-overexpressed GSH through the redox reaction, thus effectively preserving the generated free radicals in RT process, which was the second free radicals-amplifying pathway. Taken together, our study demonstrates a dual-channel parallel free radicals-amplifying RT strategy, and it is expected this work will promote the clinical application prospects of RT treatment against neuroblastoma.

Two bullets in the gun: combining immunotherapy with chemotherapy to defeat neuroblastoma by targeting adrenergic-mesenchymal plasticity

Neuroblastoma (NB) is a childhood tumor that originates in the peripheral sympathetic nervous system and is responsible for 15% of cancer-related deaths in the pediatric population. Despite intensive multimodal treatment, many patients with high-risk NB relapse and develop a therapy-resistant tumor. One of the phenomena related to therapeutic resistance is intratumor heterogeneity resulting from the adaptation of tumor cells in response to different selective environmental pressures. The transcriptional and epigenetic profiling of NB tissue has recently revealed the existence of two distinct cellular identities in the NB, termed adrenergic (ADRN) and mesenchymal (MES), which can spontaneously interconvert through epigenetic regulation. This phenomenon, known as tumor plasticity, has a major impact on cancer pathogenesis. The aim of this review is to describe the peculiarities of these two cell states, and how their plasticity affects the response to current therapeutic treatments, with special focus on the immunogenic potential of MES cells. Furthermore, we will discuss the opportunity to combine immunotherapy with chemotherapy to counteract NB phenotypic interconversion.

Toxicological profiling of a de novo synthesized benzimidazole derivative with potent and selective proapoptotic potentials against breast cancer

This study aimed to investigate the toxicological profile of 1-(6-(1H-benzo[d]imidazole-2-yl)-2-methylpyridin-3-yl) ethanone (BMPE), both in vitro and in vivo. The proapoptotic/necrotic and cell cycle arrest potentials of BMPE were assessed in MCF-7 cell line. The in vivo toxicology was assessed in female Balb/c mice by repeated dosing of 5, 25, and 50 mg/kg for 21 consecutive days, then different biochemical, inflammatory, and oxidative markers were assessed in sera/tissue homogenates of treated animals. The new derivative showed a potent selective cytotoxicity against malignant cell lines with IC50 value 0.2 μM/mL, while the cytotoxic effect on normal Wi-38 cells was observed at IC50 value 0.4 μM/mL; i.e. twofold the effective anticancer dose. BMPE exhibited an early DNA fragmentation-derived cell apoptosis observed at the G0/G1 checkpoint. In vivo, BMPE was biochemically/immunologically tolerable at a pharmacological dose range of 5-25 mg/kg, with no significant rates of mortality/morbidity and minimal-to-moderate histopathological alterations recorded. The new derivative represents an attractive therapeutic candidate for breast cancer, considering its noticeable modulatory effect on the oxidative-inflammatory axis that would relate to its potent antitumor effect.

Biological Insight and Recent Advancement in the Treatment of Neuroblastoma

One of the most frequent solid tumors in children is neuroblastoma, which has a variety of clinical behaviors that are mostly influenced by the biology of the tumor. Unique characteristics of neuroblastoma includes its early age of onset, its propensity for spontaneous tumor regression in newborns, and its high prevalence of metastatic disease at diagnosis in individuals older than 1 year of age. Immunotherapeutic techniques have been added to the previously enlisted chemotherapeutic treatments as therapeutic choices. A groundbreaking new treatment for hematological malignancies is adoptive cell therapy, specifically chimeric antigen receptor (CAR) T cell therapy. However, due to the immunosuppressive nature of the tumor microenvironment (TME) of neuroblastoma tumor, this treatment approach faces difficulties. Numerous tumor-associated genes and antigens, including the MYCN proto-oncogene (MYCN) and disialoganglioside (GD2) surface antigen, have been found by the molecular analysis of neuroblastoma cells. The MYCN gene and GD2 are two of the most useful immunotherapy findings for neuroblastoma. The tumor cells devise numerous methods to evade immune identification or modify the activity of immune cells. In addition to addressing the difficulties and potential advancements of immunotherapies for neuroblastoma, this review attempts to identify important immunological actors and biological pathways involved in the dynamic interaction between the TME and immune system.

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.

[Clinical efficacy of combined therapy in children with stage 4 neuroblastoma]

OBJECTIVES

To study the early clinical efficacy of combined therapy of stage 4 neuroblastoma.

METHODS

A retrospective analysis was performed on the medical data and follow-up data of 14 children with stage 4 neuroblastoma who were diagnosed in Hong Kong University-Shenzhen Hospital from January 2016 to June 2021.

RESULTS

The median age of onset was 3 years and 7.5 months in these 14 children. Among these children, 9 had positive results of bone marrow biopsy, 4 had N-Myc gene amplification, 13 had an increase in neuron-specific enolase, and 7 had an increase in vanilmandelic acid in urine. Based on the results of pathological examination, differentiated type was observed in 6 children, undifferentiated type in one child, mixed type, in one child and poorly differentiated type in 6 children. Of all the children, 10 received chemotherapy with the N7 regimen (including 2 children receiving arsenic trioxide in addition) and 4 received chemotherapy with the Rapid COJEC regimen. Thirteen children underwent surgery, 14 received hematopoietic stem cell transplantation, and 10 received radiotherapy. A total of 8 children received Ch14.18/CHO immunotherapy, among whom 1 child discontinued due to anaphylactic shock during immunotherapy, and the other 7 children completed Ch14.18/CHO treatment without serious adverse events, among whom 1 child was treated with Lu177 Dotatate 3 times after recurrence and is still undergoing chemotherapy at present. The median follow-up time was 45 months for all the 14 children. Four children experienced recurrence within 2 years, and the 2-year overall survival rate was 100%; 4 children experienced recurrence within 3 years, and 7 achieved disease-free survival within 3 years.

CONCLUSIONS

Multidisciplinary combined therapy is recommended for children with stage 4 neuroblastoma and can help them achieve better survival and prognosis.

Neuroblastoma-Telomere maintenance, deregulated signaling transduction and beyond

The childhood malignancy neuroblastoma belongs to the group of embryonal tumors and originates from progenitor cells of the sympathoadrenal lineage. Treatment options for children with high-risk and relapsed disease are still very limited. In recent years, an ever-growing molecular diversity was identified using (epi)-genetic profiling of neuroblastoma tumors, indicating that molecularly targeted therapies could be a promising therapeutic option. In this review article, we summarize the various molecular subtypes and genetic events associated with neuroblastoma and describe recent advances in targeted therapies. We lay a strong emphasis on the importance of telomere maintenance mechanisms for understanding tumor progression and risk classification of neuroblastoma.