Neuroblastoma Pathogenesis Research Articles

Pharmacologically Targeting Ferroptosis and Cuproptosis in Neuroblastoma.

Neuroblastoma is a deadly pediatric cancer that originates from the neural crest and frequently develops in the abdomen or adrenal gland. Although multiple approaches, including chemotherapy, radiotherapy, targeted therapy, and immunotherapy, are recommended for treating neuroblastoma, the tumor will eventually develop resistance, leading to treatment failure and cancer relapse. Therefore, a firm understanding of the molecular mechanisms underlying therapeutic resistance is vital for the development of new effective therapies. Recent research suggests that cancer-specific modifications to multiple subtypes of nonapoptotic regulated cell death (RCD), such as ferroptosis and cuproptosis, contribute to therapeutic resistance in neuroblastoma. Targeting these specific types of RCD may be viable novel targets for future drug discovery in the treatment of neuroblastoma. In this review, we summarize the core mechanisms by which the inability to properly execute ferroptosis and cuproptosis can enhance the pathogenesis of neuroblastoma. Therefore, we focus on emerging therapeutic compounds that can induce ferroptosis or cuproptosis, delineating their beneficial pharmacodynamic effects in neuroblastoma treatment. Cumulatively, we suggest that the pharmacological stimulation of ferroptosis and ferroptosis may be a novel and therapeutically viable strategy to target neuroblastoma.

Whole-Exome Sequencing Reveals Novel Candidate Driver Mutations and Potential Druggable Mutations in Patients with High-Risk Neuroblastoma.

Neuroblastoma is the most prevalent solid tumor in early childhood, with a 5-year overall survival rate of 40-60% in high-risk cases. Therefore, the identification of novel biomarkers for the diagnosis, prognosis, and therapy of neuroblastoma is crucial for improving the clinical outcomes of these patients. In this study, we conducted the whole-exome sequencing of 48 freshly frozen tumor samples obtained from the Biobank. Somatic variants were identified and selected using a bioinformatics analysis pipeline. The mutational signatures were determined using the Mutalisk online tool. Cancer driver genes and druggable mutations were predicted using the Cancer Genome Interpreter. The most common mutational signature was single base substitution 5. MUC4, MUC16, and FLG were identified as the most frequently mutated genes. Using the Cancer Genome Interpreter, we identified five recurrent cancer driver mutations spanning MUC16, MUC4, ALK, and CTNND1, with the latter being novel and containing a missense mutation, R439C. We also identified 11 putative actionable mutations including NF1 Q1798*, Q2616*, and S636X, ALK F1174L and R1275Q, SETD2 P10L and Q1829E, BRCA1 R612S, NOTCH1 D1670V, ATR S1372L, and FGFR1 N577K. Our findings provide a comprehensive overview of the novel information relevant to the underlying molecular pathogenesis and therapeutic targets of neuroblastoma.

Bioinformatics reveals the potential mechanisms and biomarkers of necroptosis in neuroblastoma.

Neuroblastoma (NB) is a malignant tumor primarily found in children, presenting significant challenges in its development and prognosis. The role of necroptosis in the pathogenesis of NB has been acknowledged as crucial for treatment. This study aimed to investigate the key genes and functional pathways associated with necroptosis, as well as immune infiltration analysis, in NB. Furthermore, we aimed to evaluate the diagnostic significance of these genes for prognostic assessment and explore their potential immunological characteristics. The NB dataset (GSE19274, GSE73517, and GSE85047) was obtained from the Gene Expression Omnibus (GEO) database, and genes associated with necroptosis were collected from GeneCards and previous literature. First, we conducted differential expression analysis and performed Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). We employed gene set enrichment analysis (GSEA) to identify overlapping enriched functional pathways from the NB dataset. In addition, we constructed a protein-protein interaction (PPI) network, predicting relevant microRNAs (miRNAs) and transcription factors (TFs), as well as their corresponding drug predictions. Furthermore, the diagnostic value was assessed using receiver operating characteristic (ROC) curves. Finally, an immune infiltration analysis was performed. We identified six necroptosis-related differentially expressed genes (NRDEGs) closely associated with necroptosis in NB. They were enriched in Tuberculosis, Apoptosis-multiple species, Salmonella infection, legionellosis, and platinum drug resistance. GSEA and PPI network analyses, along with mRNA-drug interaction network, revealed 38 potential drugs corresponding to BIRC2, CAMK2G, CASP3, and IL8. ROC curve analysis showed that in GSE19274, FLOT2 with area under the ROC curve (AUC) of 0.850 and DAPK1 with AUC of 0.789. Our study elucidates the key genes and functional pathways associated with necroptosis in NB, offering valuable insights to enhance our comprehension of the pathogenesis of NB, and improve prognosis assessment.

Blockade of Discoidin Domain Receptor Signaling with Sitravatinib Reveals DDR2 as a Mediator of Neuroblastoma Pathogenesis and Metastasis.

Oncogene-driven expression and activation of receptor tyrosine kinases promotes tumorigenesis and contributes to drug resistance. Increased expression of the kinases discoidin domain receptor 2 (DDR2), RET Proto-Oncogene (RET), Platelet Derived Growth Factor Receptor Alpha (PDGFRA), KIT Proto-Oncogene (KIT), MET Proto-Oncogene (MET), and anaplastic lymphoma kinase (ALK) independently correlate with decreased overall survival and event free survival of pediatric neuroblastoma. The multikinase inhibitor sitravatinib targets DDR2, RET, PDGFRA, KIT, and MET with low nanomolar activity and we therefore tested its efficacy against orthotopic and syngeneic tumor models. Sitravatinib markedly reduced cell proliferation and migration in vitro independently of N-Myc proto-oncogene (MYCN), ALK, or c-Myc proto-oncogene status and inhibited proliferation and metastasis of human orthotopic xenografts. Oral administration of sitravatinib to homozygous Th-MYCN transgenic mice (Th-MYCN+/+) after tumor initiation completely arrested further tumor development with no mice dying of disease while maintained on sitravatinib treatment (control cohort 57 days median time to sacrifice). Among these top kinases, DDR2 expression has the strongest correlation with poor survival and high stage at diagnosis and the highest sensitivity to the drug. We confirmed on-target inhibition of collagen-mediated activation of DDR2. Genetic knockdown of DDR2 partially phenocopies sitravatinib treatment, limiting tumor development and metastasis across tumor models. Analysis of single-cell sequencing data demonstrated that DDR2 is restricted to mesenchymal-type tumor subpopulations and is enriched in Schwann cell precursor subpopulations found in high-risk disease. These data define an unsuspected role for sitravatinib as a therapeutic agent in neuroblastoma and reveal a novel function for DDR2 as a driver of tumor growth and metastasis.

Review of Patient Gene Profiles Obtained through a Non-Negative Matrix Factorization-Based Framework to Determine the Role Inflammation Plays in Neuroblastoma Pathogenesis.

Neuroblastoma is the most common extracranial solid tumor in children. It is a highly heterogeneous tumor consisting of different subcellular types and genetic abnormalities. Literature data confirm the biological and clinical complexity of this cancer, which requires a wider availability of gene targets for the implementation of personalized therapy. This paper presents a study of neuroblastoma samples from primary tumors of untreated patients. The focus of this analysis is to evaluate the impact that the inflammatory process may have on the pathogenesis of neuroblastoma. Eighty-eight gene profiles were selected and analyzed using a non-negative matrix factorization framework to extract a subset of genes relevant to the identification of an inflammatory phenotype, whose targets (PIK3CG, NFATC2, PIK3R2, VAV1, RAC2, COL6A2, COL6A3, COL12A1, COL14A1, ITGAL, ITGB7, FOS, PTGS2, PTPRC, ITPR3) allow further investigation. Based on the genetic signals automatically derived from the data used, neuroblastoma could be classified according to stage rather than as a "cold" or "poorly immunogenic" tumor.

Extracellular vesicles in neuroblastoma: role in progression, resistance to therapy and diagnostics.

Neuroblastoma (NB) is the most common extracranial solid pediatric cancer, and is one of the leading causes of cancer-related deaths in children. Despite the current multi-modal treatment regimens, majority of patients with advanced-stage NBs develop therapeutic resistance and relapse, leading to poor disease outcomes. There is a large body of knowledge on pathophysiological role of small extracellular vesicles (EVs) in progression and metastasis of multiple cancer types, however, the importance of EVs in NB was until recently not well understood. Studies emerging in the last few years have demonstrated the involvement of EVs in various aspects of NB pathogenesis. In this review we summarize these recent findings and advances on the role EVs play in NB progression, such as tumor growth, metastasis and therapeutic resistance, that could be helpful for future investigations in NB EV research. We also discuss different strategies for therapeutic targeting of NB-EVs as well as utilization of NB-EVs as potential biomarkers.

Abstract 5988: The role of the deubiquitinase USP7 and the E3/E4 ubiquitin ligase complex ITCH/UBE4B in the regulation of cell death in neuroblastoma

Abstract Dysregulation of the Ubiquitin Proteasome System has been linked to many human diseases, including cancer. Expression of UBE4B ubiquitin ligase is associated with neuroblastoma patient outcomes and its functional roles in neuroblastoma pathogenesis are not known. We have recently identified a ubiquitin complex ITCH/UBE4B which mediates ubiquitination of Ku70 and c-FLIPL proteins for proteasomal degradation allowing HDAC inhibitor-mediated caspase-8 dependent apoptosis. We also confirmed that the deubiquitinase USP7, critical player in tumor suppression and DNA repair, can be a potential therapeutic target for neuroblastoma. Highly selective USP7 inhibitors have demonstrated significant antitumor activity in preclinical models of adult cancer, and we reported that these inhibitors alone can be more effective against neuroblastoma tumor growth. Our hypothesis is that USP7 inhibition will be more effective against neuroblastoma tumors through destabilization of ITCH/UBE4B complex protein targets allowing a stronger induction of cell death in response to treatment for the children. To evaluate efficacy of USP7 inhibitors in combination with HDAC inhibitors or chemotherapy against neuroblastoma tumor growth, neuroblastoma cell lines depleted for UBE4B or USP7 were treated with increasing concentrations of USP7 inhibitors alone or in combination with chemotherapy or with HDAC inhibitors. Cell proliferation was measured using continuous live cell imaging and apoptosis by caspase cleavage and PARP cleavage detection by western blot. We have evaluated also, whether ubiquitination/deubiquitination and degradation rates of p53, Ku70 and c-FLIPL proteins could modulate induction of apoptosis and necroptosis. USP7 inhibition resulted in decreases in cell viability in p53 wild-type neuroblastoma cell lines. USP7 inhibition induced apoptosis and necroptosis by increasing phosphorylation of MLKL, RIPK3 and RIPK1. In UBE4B or USP7 depleted cells, a huge induction of necroptosis and a small rate of apoptosis were observed. We also identified USP7 as a deubiquitinase of Ku70, stabilizing Ku70 at the basal level, leading to stabilization of Ku70/c-FLIPL/Bax complex. USP7 inhibition destabilizes ku70 and c-FLIPL for protein degradation leading to induction of apoptosis as well as necroptosis. UBE4B depletion in neuroblastoma inhibits HDAC inhibitors mediated caspase-8 mediated apoptosis but enhances necroptosis, due to the inhibition of Ku70 and c-FLIPL proteins degradation leading to the blockade of caspase-8 activation and the activation of the necroptosome. Our data suggests that USP7 and ITCH/UBE4B can control the switch between apoptosis and necroptosis in response to USP7 and HDAC inhibitors. USP7 inhibition and ITCH/UBE4B activation by HDAC inhibitors could be a promising therapeutic strategy for children with high-risk and relapsed neuroblastoma. Citation Format: Christophe Le Clorennec, CARLA SAMPAIO, PETER E. ZAGE. The role of the deubiquitinase USP7 and the E3/E4 ubiquitin ligase complex ITCH/UBE4B in the regulation of cell death in neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5988.

Abstract 149: Modeling patient-specific CHEK2 genetic variants associated with high-risk neuroblastoma

Abstract Background: Neuroblastoma (NB) is the most common extra-cranial solid tumor in children and accounts for approximately 10% of childhood cancer deaths. Recently, next-generation sequencing of patients enrolled in the SickKids Cancer Sequencing (KiCS) program revealed somatic and germline alterations in genes involved in the DNA damage response (DDR). Multiple germline and somatic pathogenic variants in CHEK2 were detected in patients with NB. Aims and Methods: To better understand potential roles for CHEK2 in NB pathogenesis, we are modeling patient-derived CHEK2 variants in an established transgenic zebrafish model of MYCN-driven NB. Using a CRISPR/Cas9 “knock-in” approach, we have generated stable zebrafish lines that are homozygous and heterozygous for variants of interest with either null, heterozygous, or wild-type tp53 functional status. We aim to assess tumor incidence, growth, and metastasis using direct visualization of disseminated EGFP+ tumor cells, as compared to MYCN over-expression only control fish. Given potential drug sensitivities, we also plan to assess the efficacy of various DDR pathway inhibitors in combination with frontline chemotherapies, which are effective in the treatment of DDR-deficient adult cancers. Results: Targeting chek2 in a tp53 null background had no significant effect on tumor incidence and growth compared to tp53 mutant control animals (p=0.1570 log-rank test). This contrasts with other patient-specific DDR models including gene targeting brca2 (p=0.0235, log-rank test), atm (p<0.001, log-rank test), and bard1 (p<0.001, log-rank test), potentially highlighting Tp53-dependent roles for Chek2 in NB formation in vivo. Through functional characterization of patient-specific CHEK2 variants in NB progression, our work will provide important preclinical information that will inform future diagnostics and therapeutic strategies for patients with high-risk NB. Citation Format: Xueting Xiong, Sarah Cohen-Gogo, Anita Villani, Adam Shlien, Meredith S. Irwin, Madeline Hayes. Modeling patient-specific CHEK2 genetic variants associated with high-risk neuroblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 149.

Abstract 5120: Direct targeting of the COMPASS complex inhibits neuroblastoma growth by inhibiting cancer stem cells

Abstract Epigenetic regulator COMPASS Complex, a histone H3K4 methyltransferase has recently been shown to be involved in multiple cancers and attaining focus as a novel therapeutic target. High-risk neuroblastoma (NB) is a heterogeneous pediatric cancer with high mortality and relapse rates. The relapse of refractory cancer is shown to be driven by cancer stem cells (CSCs), which are maintained by epigenetic malfunctions. In the present study, we determined the effects of inhibiting the COMPASS complex on NB CSCs and overall NB growth. A high-throughput shRNA screening of methyltransferases and demethylases reveals the role of COMPASS complex partners MLL1 and Menin in NB proliferation. We found that both MLL1 and Menin are overexpressed in our previously identified CD114+ NB CSCs. Further, MEN1 (gene coding Menin) expression showed an inverse correlation with overall NB patient survival and cancer progression in a comprehensive analysis of 1235 primary NB patient data. Our ChIP results show that the CSF3R gene which codes for CD114 and maintains CD114+ NB CSCs, is regulated by the presence of high H3K4me3 activating marks. Further, we used MI-503 to inhibit MLL1-Menin interaction and also developed MEN1 stable knockdown and found that both strategies significantly inhibit H3K4me3 activity in NB, particularly at the CSF3R gene promoter. This led to decreased CSF3R expression and NB CSC levels. MI-503 significantly inhibits proliferation in different NB cell lines and primary patient-derived xenograft (PDX) lines, with minimal effect on non-cancerous fibroblasts. MI-503 significantly inhibits NB cell cycle progression at the S phase, induces apoptosis, and inhibits NB 3D spheroid growth and development. Interestingly, we overserved differential selectivity of MI-503 in inducing apoptosis and in blocking the cell cycle in NB CSCs in contrast to non-CSCs. MEN1 knockdown also inhibits NB proliferation and 3D spheroid growth. Furthermore, MI-503 in a dose-dependent manner synergistically sensitizes NB to chemotherapy doxorubicin and significantly inhibits NB proliferation and spheroid growth compared to either agent alone. Further, by using the NB xenograft in vivo tumor model, we established that MI-503 significantly inhibits NB tumor growth and tumor metastasis by directly inhibiting tumor NB CSCs, without any observed toxicities. Similar results of significantly reduced tumor growth, metastasis, and NB CSCs were shown by the MEN1 knockdown in vivo. Overall, our data show that the MLL1-Menin of the COMPASS complex directly activates the CSF3R gene to maintain NB CSCs and drive NB pathogenesis. Our data show that MI-503 or MEN1 knockdown leads to significant inhibition of NB growth by directly inhibiting NB CSCs in both in vitro and in vivo tumor models. Further developing these epigenetic-based therapeutic strategies and combining them with current therapies will pave the way for effectively managing NB. Citation Format: Rameswari Chilamakuri, Saurabh Agarwal. Direct targeting of the COMPASS complex inhibits neuroblastoma growth by inhibiting cancer stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5120.

Telomere maintenance mechanisms in neuroblastoma: New insights and translational implications

The clinical behaviour of neuroblastoma ranges from spontaneous tumour regression or maturation into benign ganglioneuroma to fatal progression despite intensive treatment [1,2]. The mechanisms underlying the distinct phenotypes have remained uncertain yet. A number of recent studies noticed that activation of telomere maintenance mechanisms (TMM) in the malignant neuroblasts is strongly associated with high-risk disease and poor outcome, whereas TMM are absent in spontaneously regressing low-risk tumours, suggesting that telomere maintenance is essential to drive neuroblasts into the fully malignant state. Stabilization of the telomeres above a critical threshold is essential for cancer cells to gain replicative immortality and has thus been considered a hallmark of cancer [3]. In most high-risk neuroblastomas, TMM is conferred by induction of telomerase, either through genomic rearrangements of the TERT locus, encoding for the catalytic subunit of telomerase, or amplification of the MYCN proto-oncogene, whereas the alternative lengthening of telomeres (ALT) pathway is activated in approximately one-quarter of high-risk tumours [4–8]. We here review recent advances on our understanding of the mechanistic role of telomere maintenance in neuroblastoma pathogenesis, and discuss potential implications on neuroblastoma risk assessment and on the development of novel therapies directed against TMM.

A peptide encoded by the circular form of the SHPRH gene induces apoptosis in neuroblastoma cells.

Circular RNAs (circRNAs) and their derived peptides represent largely unchartered areas in cellular biology, with many potential roles yet to be discovered. This study aimed to elucidate the role and molecular interactions of circSHPRH and its peptide derivative SHPRH-146aa in the pathogenesis of neuroblastoma (NB). NB samples in the GSE102285 dataset were analyzed to measure circSHPRH expression, followed by in vitro experiments for validation. The role of SHPRH-146aa in NB cell proliferation, migration, and invasion was then examined, and luciferase activity assay was performed after SHPRH-146aa and RUNX1 transfection. Finally, the regulation of NB cell apoptosis by SHPRH-146aa combined with NFKBIA was tested. The GSE102285 dataset indicated overexpression of circSHPRH in NB samples, further supported by in vitro findings. Overexpression of circ-SHPRH and SHPRH-146aa inhibited proliferation, migration, and invasion of NB cells. A significant increase in apoptosis was observed, with upregulation of Caspase-3 and downregulation of Bcl-2. Furthermore, the peptide derivative SHPRH-146aa, derived from circSHPRH, suppressed NB cell malignancy traits, suggesting its role as a therapeutic target. A direct interaction between SHPRH-146aa and the transcription factor RUNX1 was identified, subsequently leading to increased NFKBIA expression. Notably, NFKBIA knockdown inhibited the pro-apoptotic effect of SHPRH-146aa on NB cells. The study demonstrates that circ-SHPRH and SHPRH-146aa play significant roles in inhibiting the malignant progression of NB. They induce apoptosis primarily by modulating key apoptotic proteins Caspase-3 and Bcl-2, a process that appears to be regulated by NFKBIA. The SHPRH-146aa-RUNX1 interaction further elucidates a novel pathway in the regulation of apoptosis in NB. These findings indicate that circ-SHPRH and its derived peptide SHPRH-146aa could be potential therapeutic targets for NB treatment.

EIF2S1 Silencing Impedes Neuroblastoma Development Through GPX4 Inactivation and Ferroptosis Induction.

Background: Neuroblastoma (NB) is one of the most devastating malignancies in children, accounting for a high mortality rate due to limited treatment options. This study is aimed at elucidating the role of the ferroptosis-related EIF2S1 gene in NB pathogenesis and exploring its potential as a therapeutic target. Methods: We conducted comprehensive bioinformatics analyses utilizing the FerrDb database and NB-related transcriptomics data to investigate the role of EIF2S1 in NB. Changes in EIF2S1 expression were subsequently validated in NB tissues and cell lines. Loss-of-function experiments were performed in SK-N-SH and IMR-32 cell lines through shRNA-mediated EIF2S1 knockdown. The impact of EIF2S1 knockdown on the tumorigenesis of SK-N-SH cells was assessed in nude mice. Results: Bioinformatics analyses revealed a significant association between elevated EIF2S1 expression and poor prognosis in NB patients. The increased levels of EIF2S1 expression were confirmed in NB tissues and cancerous cell lines. Furthermore, EIF2S1 overexpression was linked to translational regulation and immune cell infiltration modulation. Silencing of EIF2S1 resulted in the suppression of cell proliferation, migration, and tumorigenicity in NB cells. Additionally, EIF2S1 knockdown led to an accumulation of iron and oxidative stress, as well as a reduction in GPX4 and SLC7A11 expression. Conclusion: Our findings indicate that EIF2S1 appears to facilitate the progression of NB by protecting tumor cells from ferroptosis through modulating GPX4 and SLC7A11 expression. Consequently, EIF2S1 may serve as a potential therapeutic target for the management of NB.

UBE4B interacts with the ITCH E3 ubiquitin ligase to induce Ku70 and c-FLIPL polyubiquitination and enhanced neuroblastoma apoptosis.

Expression of the UBE4B ubiquitin ligase is strongly associated with neuroblastoma patient outcomes, but the functional roles of UBE4B in neuroblastoma pathogenesis are not known. We evaluated interactions of UBE4B with the E3 ubiquitin ligase ITCH/AIP4 and the effects of UBE4B expression on Ku70 and c-FLIPL ubiquitination and proteasomal degradation by co-immunoprecipitation and Western blots. We also evaluated the role of UBE4B in apoptosis induced by histone deacetylase (HDAC) inhibition using Western blots. UBE4B binding to ITCH was mediated by WW domains in the ITCH protein. ITCH activation led to ITCH-UBE4B complex formation and recruitment of Ku70 and c-FLIPL via ITCH WW domains, followed by Ku70 and c-FLIPL Lys48/Lys63 branched polyubiquitination and proteasomal degradation. HDAC inhibition induced Ku70 acetylation, leading to release of c-FLIPL and Bax from Ku70, increased Ku70 and c-FLIPL Lys48/Lys63 branched polyubiquitination via the ITCH-UBE4B complex, and induction of apoptosis. UBE4B depletion led to reduced polyubiquitination and increased levels of Ku70 and c-FLIPL and to reduced apoptosis induced by HDAC inhibition via stabilization of c-FLIPL and Ku70 and inhibition of caspase 8 activation. Our results have identified novel interactions and novel targets for UBE4B ubiquitin ligase activity and a direct role for the ITCH-UBE4B complex in responses of neuroblastoma cells to HDAC inhibition, suggesting that the ITCH-UBE4B complex plays a critical role in responses of neuroblastoma to therapy and identifying a potential mechanism underlying the association of UBE4B expression with neuroblastoma patient outcomes.

Molecular genetic traits and risk factors for neuroblastoma

Neuroblastoma is the most common extracranial solid tumor in childhood, accounting for 815% of all malignant neoplasms in children. The uniqueness of the neuroblastoma etiology and pathogenesis creates significant difficulties for doctors due to the unpredictability of the course of the disease: the tumor can regress and lead to death in a short time, showing significant immunity to ongoing therapy. Early diagnosis of a tumor is necessary to understand the risk factors, the etiology, the mechanisms of neuroblastoma occurrence and further development. To date, a number of different risk factors have been identified, related both to genetic aspects and to aspects related to the course of pregnancy, birth and lifestyle of the childs parents. The list of these risk factors is still incomplete and research to identify new factors continues to this day. Morphological and molecular genetic diagnostics play an important role in this. Undifferentiated and low-differentiated variants of neuroblastoma are often associated with MYCN amplification and other chromosomal aberrations determined by molecular genetic research. Chromosomal instability plays an important role in the process of early tumor development, which probably causes the possibility of acquiring certain genetic changes, which also determines the prognosis and further therapeutic options. In this article, we have identified the most significant risk factors by comparing the results of various studies.

Unraveling the Mystery: Next Generation Sequencing Sheds Light on Neuroblastoma Pathogenesis and Targeted Therapies.

There is considerable interest in the molecular evaluation of solid tumors in pediatric cases. Although clinical trials are in progress for targeted therapies against neuroblastoma (NB), novel therapeutic strategies are needed for high-risk cases that are resistant to therapy. The aim of the present study was to document the specific gene mutations related to targeted therapy in relapsed or refractory NB patients by using next generation sequencing (NGS). The study included 57 NB patients from amongst 1965 neuroblastic cases in Turkey who experienced a recurrence after multi-model therapy. The cases were diagnosed, risk-stratified, and treated according to the classification system from the International Neuroblastoma Risk Group. Single nucleotide variations in 60 genes were investigated using the Pillar Onco/Reveal Multicancer v4 panel and Pillar RNA fusion panel on the Illumina Miniseq platform. ERBB2 I655V was the most frequent mutation and was found in 39.65% of cases. Anaplastic Lymphoma Kinase (ALK) mutations (F1174L, R1275Q, and rare mutations in the tyrosine kinase domain) were detected in 29.3% of cases. Fusion mutations in NTRK1, NTRK3, ROS1, RET, FGFR3, ALK and BRAF were observed in 19.6% of cases. This study presents valuable mutation data for relapsed and refractory NB patients. The high frequency of the ERBB2 I655V mutation may allow further exploration of this mutation as a potential therapeutic target. Rare BRAF mutations may also provide opportunities for targeted therapy. The role of ABL1 mutations in NB should also be explored further.

FAM201A encodes small protein NBASP to inhibit neuroblastoma progression via inactivating MAPK pathway mediated by FABP5

Increasing evidence indicates that long non-coding RNA (lncRNA) is one of the most important RNA regulators in the pathogenesis of neuroblastoma (NB). Here, we found that FAM201A was low expressed in NB and a variety of gain and loss of function studies elucidated the anti-tumor effects of FAM201A on the regulation of proliferation, migration and invasion of NB cells. Intriguingly, we identified the ability of FAM201A to encode the tumor-suppressing protein, NBASP, which interacted with FABP5 and negatively regulated its expression. In vivo assays also revealed NBASP repressed NB growth via inactivating MAPK pathway mediated by FABP5. In conclusion, our findings demonstrated that NBASP encoded by FAM201A played a tumor-suppressor role in NB carcinogenesis via down-regulating FABP5 to inactivate the MAPK pathway. These results extended our understanding of the relationship of lncRNA-encoded functional peptides and plasticity of tumor progression.

Defining the landscape of circular RNAs in neuroblastoma unveils a global suppressive function of MYCN

Circular RNAs (circRNAs) are a regulatory RNA class. While cancer-driving functions have been identified for single circRNAs, how they modulate gene expression in cancer is not well understood. We investigate circRNA expression in the pediatric malignancy, neuroblastoma, through deep whole-transcriptome sequencing in 104 primary neuroblastomas covering all risk groups. We demonstrate that MYCN amplification, which defines a subset of high-risk cases, causes globally suppressed circRNA biogenesis directly dependent on the DHX9 RNA helicase. We detect similar mechanisms in shaping circRNA expression in the pediatric cancer medulloblastoma implying a general MYCN effect. Comparisons to other cancers identify 25 circRNAs that are specifically upregulated in neuroblastoma, including circARID1A. Transcribed from the ARID1A tumor suppressor gene, circARID1A promotes cell growth and survival, mediated by direct interaction with the KHSRP RNA-binding protein. Our study highlights the importance of MYCN regulating circRNAs in cancer and identifies molecular mechanisms, which explain their contribution to neuroblastoma pathogenesis.

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.

Back to the future: evolutionary biology reveals a key regulatory switch in neuroblastoma pathogenesis.

While MYCN expression is an important contributing factor to heterogeneity in the natural history of neuroblastoma (NBL), a mechanistic understanding of this often mutationally quiet tumor has remained elusive. In this issue of the JCI, Weichert-Leahey and authors focused on the adrenergic and mesenchymal core regulatory circuitries (CRC) as NBL transcriptional programs. The authors previously showed that overexpression of LIM-domain-only 1 (LMO1), a transcriptional coregulator, synergizes with MYCN to accelerate tumor formation and metastasis in an NBL-zebrafish model. They now demonstrate experimentally, using genome-edited zebrafish, that a polymorphism in the human rs2168101 locus of the LMO1 gene determines which CRC is active in a tumor. In some cases, LMO3 compensated for LMO1 loss and drove the adrenergic CRC in MYCN-positive NBL. This study exemplifies the value of evolutionary relationships and zebrafish models in the investigation of human disease and reveals pathways of NBL development that may affect prevention or intervention strategies.

Recent advances and application value of circRNA in neuroblastoma.

Neuroblastoma (NB) is children's most prevalent solid malignant tumor, accounting for 15% of childhood cancer mortality. Non-coding RNA is important in NB pathogenesis. As a newly identified non-coding RNA, abnormal regulation (abnormal up-regulation or down-regulation) of the circRNAs expression is implicated in the tumorigenesis of various tumors, including NB. CircRNAs primarily regulate the expression of microRNA (miRNA) target genes by microRNA (miRNA) sponge adsorption. Clinical evidence suggests that the expression of certain circRNAs is associated with the prognosis and clinical features of NB and hence may be exploited as a biomarker or therapeutic target. This review examines circRNAs that have been demonstrated to play a function in NB.