Genetic predisposition and chromosome instability in neuroblastoma

Risk of developing neuroblastoma influenced by maternal stressful life events during pregnancy and congenital pathologies

OBJECTIVE

A retrospective multicenter study to investigate the potential association between descriptive information related to pregnancy history and perinatal features and the risk of neuroblastoma (NB) in children.

STUDY DESIGN

Data from 56 mothers during 105 pregnancies (56 cases of NB, 49 control siblings) were collected through face-to-face or telephone interviews with mothers of children diagnosed with NB, along with information extracted from Health System databases. Descriptive information related to (a) pregnancy history as maternal stressful life events with perceived distress during pregnancy, weight gain, alcohol and tobacco consumption, mode of delivery and gestational age; and (b) perinatal features as congenital pathologies, weight at birth and type of feeding were examined to identify potential risk factors for NB.

RESULTS

Stressful life events during pregnancy and certain congenital pathologies were independently associated with NB risk. No significant associations were found between other features. Breastfeeding rates were similar between cases and controls.

CONCLUSION

Our results underscore the importance of providing support and care to pregnant women to reduce potential stressors. Further research is needed to better understand the influence of dysbiosis and mitochondrial-nuclear communication impairment as underlying mechanisms of maternal stress during pregnancy and presence of congenital pathologies in order to confirm them as potential risk factors for NB.

Integrative genomic analyses identify neuroblastoma risk genes involved in neuronal differentiation

Genome-Wide Association Studies (GWAS) have been decisive in elucidating the genetic predisposition of neuroblastoma (NB). The majority of genetic variants identified in GWAS are found in non-coding regions, suggesting that they can be causative of pathogenic dysregulations of gene expression. Nonetheless, pinpointing the potential causal genes within implicated genetic loci remains a major challenge. In this study, we integrated NB GWAS and expression Quantitative Trait Loci (eQTL) data from adrenal gland to identify candidate genes impacting NB susceptibility. We found that ZMYM1, CBL, GSKIP and WDR81 expression was dysregulated by NB predisposing variants. We further investigated the functional role of the identified genes through computational analysis of RNA sequencing (RNA-seq) data from single-cell and whole-tissue samples of NB, neural crest, and adrenal gland tissues, as well as through in vitro differentiation assays in NB cell cultures. Our results indicate that dysregulation of ZMYM1, CBL, GSKIP, WDR81 may lead to malignant transformation by affecting early and late stages of normal program of neuronal differentiation. Our findings enhance the understanding of how specific genes contribute to NB pathogenesis by highlighting their influence on neuronal differentiation and emphasizing the impact of genetic risk variants on the regulation of genes involved in critical biological processes.

Synaptic vesicle protein 2-targeted doxorubicin-loaded liposome for effective neuroblastoma therapy

Neuroblastoma, a pediatric cancer originating from neural crest tissues of the sympathetic nervous system, poses significant treatment challenges due to its molecular diversity and restricted druggable targets. While chemotherapy is a common treatment, its drawbacks, including poor targeting of cancer cells and nonspecific cytotoxicity, highlight the urgent need for innovative and effective therapeutic strategies. Herein, we developed a novel drug by coupling the receptor binding domain of botulinum neurotoxin type A (Hc) fused with monomeric streptavidin (mSA) to biotin coated doxorubicin (Dox)-loaded liposome, via interaction between mSA and biotin. The resultant Hc-coated liposome (Hc-Lipo@Dox) actively targeted the recycling synaptic vesicle 2 protein (SV2) abundantly expressed on the surface of neuroblastoma cells. Our results revealed that Hc-Lipo@Dox more effectively entered the neuroblastoma SH-SY5Y cells, inducing apoptosis compared to non-targeted liposome and free Dox. Moreover, Hc-Lipo@Dox rapidly enriched Dox in the subcutaneously implanted neuroblastoma tumor in nude mice, resulting potent anti-neuroblastoma effect compared to non-targeted liposomes or free Dox. Importantly, Hc-Lipo@Dox significantly improved the survival rate of treated mice, while also exhibiting a favorable safety profile with no discernible impact on mobility or observable side effects. These findings highlight the potential of SV2-targeted Dox liposome as a promising and well-tolerated chemotherapy approach for neuroblastoma treatment. Moreover, the technology established here has broader applications for various cancer therapies by substituting the Hc moiety with other tumor-specific targeting moieties.

Super-enhancer-driven IRF2BP2 enhances ALK activity and promotes neuroblastoma cell proliferation

BACKGROUND

Super-enhancers (SEs) typically govern the expression of critical oncogenes and play a fundamental role in the initiation and progression of cancer. Focusing on genes that are abnormally regulated by SE in cancer may be a new strategy for understanding pathogenesis. In the context of this investigation, we have identified a previously unreported SE-driven gene IRF2BP2 in neuroblastoma (NB).

METHODS

The expression and prognostic value of IRF2BP2 were detected in public databases and clinical samples. The effect of IRF2BP2 on NB cell growth and apoptosis was evaluated through in vivo and in vitro functional loss experiments. The molecular mechanism of IRF2BP2 was investigated by the study of chromatin regulatory regions and transcriptome sequencing.

RESULTS

The sustained high expression of IRF2BP2 results from the activation of a novel SE established by NB master transcription factors MYCN, MEIS2, and HAND2, and they form a new complex that regulates the gene network associated with the proliferation of NB cell populations. We also observed a significant enrichment of the AP-1 family at the binding sites of IRF2BP2. Remarkably, within NB cells, AP-1 plays a pivotal role in shaping the chromatin accessibility landscape, thereby exposing the binding site for IRF2BP2. This orchestrated action enables AP-1 and IRF2BP2 to collaboratively stimulate the expression of the NB susceptibility gene ALK, thereby upholding the highly proliferative phenotype characteristic of NB.

CONCLUSIONS

Our findings indicate that SE-driven IRF2BP2 can bind to AP-1 to maintain the survival of tumor cells via regulating chromatin accessibility of the NB susceptibility gene ALK.

Long-Term Risk of Subsequent Neoplasms in 5-Year Survivors of Childhood Neuroblastoma: A Dutch Childhood Cancer Survivor Study-LATER 3 Study

PURPOSE

Neuroblastoma survivors have an increased risk of developing subsequent malignant neoplasms (SMNs), but the risk of subsequent nonmalignant neoplasms (SNMNs) and risk factors are largely unknown. We analyzed the long-term risks and associated risk factors for developing SMNs and SNMNs in a well-characterized cohort of 5-year neuroblastoma survivors.

METHODS

We included 563 5-year neuroblastoma survivors from the Dutch Childhood Cancer Survivor Study (DCCSS)-LATER cohort, diagnosed during 1963-2014. Subsequent neoplasms were ascertained by linkages with the Netherlands Cancer Registry and the Dutch Nationwide Pathology Databank (Palga) and medical chart review. We calculated standardized incidence ratios (SIRs), absolute excess risk (AER), and cumulative incidences. Multivariable competing risk regression analysis was used to evaluate risk factors.

RESULTS

In total, 23 survivors developed an SMN and 60 an SNMN. After a median follow-up of 23.7 (range, 5.0-56.3) years, the risk of SMN was elevated compared with the general population (SIR, 4.0; 95% CI, 2.5 to 5.9; AER per 10,000 person-years, 15.1). The 30-year cumulative incidence was 3.4% (95% CI, 1.9 to 6.0) for SMNs and 10.4% (95% CI, 7.3 to 14.8) for SNMNs. Six survivors developed an SMN after iodine-metaiodobenzylguanidine (131IMIBG) treatment. Survivors treated with 131IMIBG had a higher risk of developing SMNs (subdistribution hazard ratio [SHR], 5.7; 95% CI, 1.8 to 17.8) and SNMNs (SHR, 2.6; 95% CI, 1.2 to 5.6) compared with survivors treated without 131IMIBG; results for SMNs were attenuated in high-risk patients only (SMNs SHR, 3.6; 95% CI, 0.9 to 15.3; SNMNs SHR, 1.5; 95% CI, 0.7 to 3.6).

CONCLUSION

Our results demonstrate that neuroblastoma survivors have an elevated risk of developing SMNs and a high risk of SNMNs. 131IMIBG may be a treatment-related risk factor for the development of SMN and SNMN, which needs further validation. Our results emphasize the need for awareness of subsequent neoplasms and the importance of follow-up care.

A phenome-wide association study of polygenic scores for selected childhood cancer: Results from the UK Biobank

The aim of this study was to scan phenotypes in adulthood associated with polygenic risk scores (PRS) for childhood cancers with well-articulated genetic architectures-acute lymphoblastic leukemia (ALL), Ewing sarcoma, and neuroblastoma-to examine genetic pleiotropy. Furthermore, we aimed to determine which SNPs could drive associations. Per-SNP summary statistics were extracted for PRS calculation. Participants with white British ancestry were exclusively included for analyses. SNPs were queried from the UK Biobank genotype imputation data. Records from the cancer registry, death registry, and inpatient diagnoses were abstracted for phenome-wide scans. Firth logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) alongside corresponding p values, adjusting for age at recruitment and sex. A total of 244,332 unrelated white British participants were included. We observed a significant association between ALL-PRS and ALL (OR: 1.20e+24, 95% CI: 9.08e+14-1.60e+33). In addition, we observed a significant association between high-risk neuroblastoma PRS and nonrheumatic aortic valve disorders (OR: 43.9, 95% CI: 7.42-260). There were no significant phenotype associations with Ewing sarcoma and neuroblastoma PRS. Regarding individual SNPs, rs17607816 increased the risk of ALL (OR: 6.40, 95% CI: 3.26-12.57). For high-risk neuroblastoma, rs80059929 elevated the risk of atrioventricular block (OR: 3.04, 95% CI: 1.85-4.99). Our findings suggest that individuals with genetic susceptibility to ALL may face a lifelong risk for developing ALL, along with a genetic pleiotropic association between high-risk neuroblastoma and circulatory diseases.

Neuroblastoma susceptibility and association of N7-methylguanosine modification gene polymorphisms: multi-center case-control study

BACKGROUND

Neuroblastoma (NB) is a common extracranial solid malignancy in children. The N7-methylguanosine (m7G) modification gene METTL1/WDR4 polymorphisms may serve as promising molecular markers for identifying populations susceptible to NB.

METHODS

TaqMan probes was usded to genotype METTL1/WDR4 single nucleotide polymorphisms (SNPs) in 898 NB patients and 1734 healthy controls. A logistic regression model was utilized to calculate the odds ratio (OR) and 95% confidence interval (CI), evaluating the association between genotype polymorphisms and NB susceptibility. The analysis was also stratified by age, sex, tumor origin site, and clinical stage.

RESULTS

Individual polymorphism of the METTL1/WDR4 gene investigated in this study did not show significant associations with NB susceptibility. However, combined genotype analysis revealed that carrying all 5 WDR4 protective genotypes was associated with a significantly lower NB risk compared to having 0-4 protective genotypes (AOR = 0.82, 95% CI = 0.69-0.96, P = 0.014). Further stratified analyses revealed that carrying 1-3 METTL1 risk genotypes, the WDR4 rs2156316 CG/GG genotype, the WDR4 rs2248490 CG/GG genotype, and having all five WDR4 protective genotypes were all significantly correlated with NB susceptibility in distinct subpopulations.

CONCLUSIONS

In conclusion, our findings suggest significant associations between m7G modification gene METTL1/WDR4 SNPs and NB susceptibility in specific populations.

IMPACT

Genetic variation in m7G modification gene is associated with susceptibility to NB. Single nucleotide polymorphisms in METTL1/WDR4 are associated with susceptibility to NB. Single nucleotide polymorphisms of METTL1/WDR4 can be used as a biomarker for screening NB susceptible populations.

Causal Relationship between Sex Hormone-Binding Globulin and Risk of Neuroblastoma: A Bidirectional Two-Sample Mendelian Randomization Study

BACKGROUND

The causal relationship between sex hormone-binding globulin (SHBG) and neuroblastoma remains unknown. This study aimed to explore the causality between SHBG and the risk of neuroblastoma using bidirectional two-sample Mendelian randomization (MR) study.

METHODS

Instrumental variables associated with SHBG were obtained from the genome-wide association study (GWAS) of European containing 214,989 females and 185,221 males from the UK Biobank. Summary-level data for neuroblastoma were derived from the IEU OpenGWAS project with 1,627 patients and 3,254 controls. The inverse-variance weighted (IVW) method served as the primary analytic tool.

RESULTS

The IVW method revealed a significant positive causal relationship between male SHBG and the risk of neuroblastoma [OR, 2.169; 95% confidence interval (CI), 1.207-3.897; P = 0.010]. Conversely, female SHBG showed no significant causal link with neuroblastoma (IVW OR, 1.004; 95% CI, 0.542-1.860; P = 0.990). No significant reverse causality was detected. Sensitivity analyses validated these findings.

CONCLUSIONS

Elevated SHBG levels in males, but not in females, can causally increase the risk of neuroblastoma. This gender-specific effect indicates a potential differential role of SHBG in the etiology of neuroblastoma. Further research is needed to elucidate the underlying mechanisms of this gender disparity. Monitoring SHBG levels, especially in males, could be pivotal in neuroblastoma risk assessment and management.

IMPACT

This study highlights a novel gender-specific aspect in the risk of neuroblastoma, emphasizing the potential role of male SHBG levels in neuroblastoma incidence, and sets the stage for targeted preventative strategies and further investigation into gender-based biological mechanisms.

TET3 gene rs828867 G>A polymorphism reduces neuroblastoma risk in Chinese children

Objective

Neuroblastoma (NB) is a prevalent pediatric tumor originating from primordial neural crest cells. As one of the latest epigenetics investigations focuses, RNA 5-methylcytosine (m5C) is closely related to cancer risk. TET methylcytosine dioxygenase 3 (TET3) is a demethylase for m5C modification. Whether there is an association between TET3 gene polymorphisms and neuroblastoma risk remains unclear.

Methods

We conducted an epidemiological study in 402 patients and 473 controls to evaluate the relationship between TET3 gene SNPs (rs7560668 T > C, rs828867 G > A, and rs6546891 A > G) and NB susceptibility.

Results

Our results showed that rs828867 G > A significantly reduced NB risk in Chinese children [GA vs. GG, adjusted odds ratio (OR) = 0.72, 95% confidence interval (CI) = 0.52-0.98, P=0.040; GA/AA vs. GG, adjusted OR = 0.74, 95% CI = 0.55-0.998, P=0.048]. Individuals with 2-3 risk genotypes had a significantly higher NB risk than those with 0-1 risk genotypes (adjusted OR = 1.40, 95% CI = 1.04-1.88, P=0.027). The stratified analysis showed that the rs828867 G > A associated with decreased NB risk is remarkable among children aged >18 months (adjusted OR = 0.67, 95% CI = 0.46-0.96, P=0.029) and patients at clinical III + IV stages (adjusted OR = 0.67, 95% CI = 0.45-0.98, P=0.040). Compared with the 0-1 risk genotype, the concurrence of 2-3 risk genotypes significantly increased NB risk in the following subgroups: children aged >18 months and patients at clinical III + IV stages. GTEx analysis suggested that rs828867 G > A was significantly associated with RP11-287D1.4 and POLE4 mRNA expression.

Conclusions

Overall, our results revealed that rs828867 G > A in the TET3 gene is significantly associated with predisposition to NB.

Revolutionizing pediatric neuroblastoma treatment: unraveling new molecular targets for precision interventions

Neuroblastoma (NB) is the most frequent solid tumor in pediatric cases, contributing to around 15% of childhood cancer-related deaths. The wide-ranging genetic, morphological, and clinical diversity within NB complicates the success of current treatment methods. Acquiring an in-depth understanding of genetic alterations implicated in the development of NB is essential for creating safer and more efficient therapies for this severe condition. Several molecular signatures are being studied as potential targets for developing new treatments for NB patients. In this article, we have examined the molecular factors and genetic irregularities, including those within insulin gene enhancer binding protein 1 (ISL1), dihydropyrimidinase-like 3 (DPYSL3), receptor tyrosine kinase-like orphan receptor 1 (ROR1) and murine double minute 2-tumor protein 53 (MDM2-P53) that play an essential role in the development of NB. A thorough summary of the molecular targeted treatments currently being studied in pre-clinical and clinical trials has been described. Recent studies of immunotherapeutic agents used in NB are also studied in this article. Moreover, we explore potential future directions to discover new targets and treatments to enhance existing therapies and ultimately improve treatment outcomes and survival rates for NB patients.

TRIM59-mediated ferroptosis enhances neuroblastoma development and chemosensitivity through p53 ubiquitination and degradation

Neuroblastoma, predominantly afflicting young individuals, is characterized as an embryonal tumor, with poor prognosis primarily attributed to chemoresistance. This study delved into the impact of tripartite motif (TRIM) 59, an E3 ligase, on neuroblastoma development and chemosensitivity through mediating ferroptosis and the involvement of the tumor suppressor p53. Clinical samples were assessed for TRIM59 and p53 levels to explore their correlation with neuroblastoma differentiation. In neuroblastoma cells, modulation of TRIM59 expression, either through overexpression or knockdown, was coupled with doxorubicin hydrochloride (DOX) or ferrostatin-1 (Fer-1) therapy. In vivo assessments examined the influence of TRIM59 knockdown on neuroblastoma chemosensitivity to DOX. Co-immunoprecipitation and ubiquitination assays investigated the association between TRIM59 and p53. Proliferation was gauged with Cell Counting Kit-8, lipid reactive oxygen species (ROS) were assessed via flow cytometry, and protein levels were determined by Western blotting. TRIM59 expression was inversely correlated with neuroblastoma differentiation and positively linked to cell proliferation in response to DOX. Moreover, TRIM59 impeded lipid ROS generation and ferroptosis by directly interacting with p53, promoting its ubiquitination and degradation in DOX-exposed neuroblastoma cells. Fer-1 countered the impact of TRIM59 knockdown on neuroblastoma, while TRIM59 knockdown enhanced the therapeutic efficacy of DOX in xenograph mice. This study underscores TRIM59 as an oncogene in neuroblastoma, fostering growth and chemoresistance by suppressing ferroptosis through p53 ubiquitination and degradation. TRIM59 emerges as a potential strategy for neuroblastoma therapy.

From the identification of actionable molecular targets to the generation of faithful neuroblastoma patient-derived preclinical models

BACKGROUND

Neuroblastoma (NB) represents the most frequent and aggressive form of extracranial solid tumor of infants. Although the overall survival of patients with NB has improved in the last years, more than 50% of high-risk patients still undergo a relapse. Thus, in the era of precision/personalized medicine, the need for high-risk NB patient-specific therapies is urgent.

METHODS

Within the PeRsonalizEd Medicine (PREME) program, patient-derived NB tumors and bone marrow (BM)-infiltrating NB cells, derived from either iliac crests or tumor bone lesions, underwent to histological and to flow cytometry immunophenotyping, respectively. BM samples containing a NB cells infiltration from 1 to 50 percent, underwent to a subsequent NB cells enrichment using immune-magnetic manipulation. Then, NB samples were used for the identification of actionable targets and for the generation of 3D/tumor-spheres and Patient-Derived Xenografts (PDX) and Cell PDX (CPDX) preclinical models.

RESULTS

Eighty-four percent of NB-patients showed potentially therapeutically targetable somatic alterations (including point mutations, copy number variations and mRNA over-expression). Sixty-six percent of samples showed alterations, graded as "very high priority", that are validated to be directly targetable by an approved drug or an investigational agent. A molecular targeted therapy was applied for four patients, while a genetic counseling was suggested to two patients having one pathogenic germline variant in known cancer predisposition genes. Out of eleven samples implanted in mice, five gave rise to (C)PDX, all preserved in a local PDX Bio-bank. Interestingly, comparing all molecular alterations and histological and immunophenotypic features among the original patient's tumors and PDX/CPDX up to second generation, a high grade of similarity was observed. Notably, also 3D models conserved immunophenotypic features and molecular alterations of the original tumors.

CONCLUSIONS

PREME confirms the possibility of identifying targetable genomic alterations in NB, indeed, a molecular targeted therapy was applied to four NB patients. PREME paves the way to the creation of clinically relevant repositories of faithful patient-derived (C)PDX and 3D models, on which testing precision, NB standard-of-care and experimental medicines.

Transmembrane serine protease 6, a novel target for inhibition of neuronal tumor growth

Transmembrane serine protease 6 (Tmprss6) has been correlated with the occurrence and progression of tumors, but any specific molecular mechanism linking the enzyme to oncogenesis has remained elusive thus far. In the present study, we found that Tmprss6 markedly inhibited mouse neuroblastoma N2a (neuro-2a) cell proliferation and tumor growth in nude mice. Tmprss6 inhibits Smad1/5/8 phosphorylation by cleaving the bone morphogenetic protein (BMP) co-receptor, hemojuvelin (HJV). Ordinarily, phosphorylated Smad1/5/8 binds to Smad4 for nuclear translocation, which stimulates the expression of hepcidin, ultimately decreasing the export of iron through ferroportin 1 (FPN1). The decrease in cellular iron levels in neuro-2a cells with elevated Tmprss6 expression limited the availability of the metal forribo nucleotide reductase activity, thereby arresting the cell cycle prior to S phase. Interestingly, Smad4 promoted nuclear translocation of activating transcription factor 3 (ATF3) to activate the p38 mitogen-activated protein kinases signaling pathway by binding to ATF3, inducing apoptosis of neuro-2a cells and inhibiting tumor growth. Disruption of ATF3 expression significantly decreased apoptosis in Tmprss6 overexpressed neuro-2a cells. Our study describes a mechanism whereby Tmprss6 regulates the cell cycle and apoptosis. Thus, we propose Tmprss6 as a candidate target for inhibiting neuronal tumor growth.

Risk factors and novel predictive models for metastatic neuroblastoma in children

INTRODUCTION

Neuroblastoma (NB) with distant metastasis (DM) is a high-risk condition with a poor prognosis. Early identify the risk and prognostic differences of DM in children, which is helpful for the development of clinical diagnosis and treatment.

METHODS

The study cohort included patients with NB in surveillance, epidemiological, and final outcome databases between 2010 and 2018. To identify the risk and prognostic factors for DM, both univariate and multivariate logistic and Cox regression analyses were conducted. In addition, we created and verified three online clinical prediction models. Finally, we assess the performance of the proposed predictive model.

RESULTS

Among the 1224 children with NB included in the study, 599 developed DM. Primary site is the most important factor affecting metastasis and prognosis. The training and validation groups of the diagnostic nomograms had area under curves (AUC) values of 0.872 and 0.824, respectively. In addition, in the training group, the AUC values at 12, 36, and 60 months were 0.68, 0.71, and 0.75 for the OS nomogram and 0.70, 0.72, and 0.75 for the CSS nomogram. In the validation group, the AUC values at 12, 36, and 60 months were 0.68, 0.72, and 0.70 for the OS nomogram and 0.67, 0.71, and 0.69 for the CSS nomogram, respectively. Calibration curve and decision curve analyses revealed good performance of the nomogram.

CONCLUSIONS

The nomogram developed in this study could appropriately predict DM and assess its prognosis in patients with NB.

Activation of the p53 signaling pathway by piRNA-MW557525 overexpression induces a G0/G1 phase arrest thus inhibiting neuroblastoma growth

BACKGROUND

Neuroblastoma (NB) is the most common extracranial malignant solid tumor in children. Due to drug resistance to radiotherapy and chemotherapy, mainly due to the existence of cancer stem cells (CSCs), some children still have a poor prognosis. Therefore, researchers have focused their attention on CSCs. Our research group successfully constructed cancer stem cell-like cells named Piwil2-iCSCs by reprogramming human preputial fibroblasts (FBs) with the PIWIL2 gene in the early stage, and Piwil2-iCSCs were confirmed to induce the formation of embryonic tumors. PiRNAs, noncoding small RNAs that interact with PIWI proteins, play important roles in a variety of tumors. Therefore, our study aimed to explore the role of differentially expressed (DE) piRNAs derived from sequencing of Piwil2-iCSCs in NB.

METHODS

The DE piRNAs in Piwil2-iCSCs were screened using high-throughput sequencing and further verified in NB tissues and cells. An unknown piRNA, named piRNA-MW557525, showed obvious downregulation in NB. Thus we studied the effect of piRNA-MW557525 on the biological behavior of NB through in vitro and in vivo experiments. On this basis, we successfully constructed a stably transfected NB cell line overexpressing piRNA-MW557525 and performed transcriptome sequencing to further explore the mechanism of piRNA-MW557525 in NB.

RESULTS

In vitro, piRNA-MW557525 inhibited NB cell proliferation, migration and invasion and induced apoptosis; in vivo, piRNA-MW557525 significantly reduced the volume and weight of tumors and inhibited their proliferation, migration and invasion. piRNA-MW557525 overexpression induced G0/G1 phase arrest in NB cells via activation of the P53-P21-CDK2-Cyclin E signaling pathway thus inhibiting NB growth.

CONCLUSIONS

Our findings show that piRNA-MW557525 functions as a tumor suppressor gene in NB and may serve as an innovative biomarker and possible therapeutic target for NB.

Design, syntheses, theoretical calculations, MM-GBSA, potential anti-cancer and enzyme activities of novel Schiff base compounds

In this study, new Schiff base compounds (SB-F-OH, SB-Cl-OH and SB-Br-OH) were derived from chalcone-derived amine compounds containing halogen groups and 4-hydroxybenzaldehyde. Also, their phthalonitrile compounds (SB-F-CN, SB-Cl-CN and SB-Br-CN) have been synthesized. The structures of these compounds were elucidated by NMR, FT-IR and Mass spectroscopic methods. The quantum chemical parameters were calculated at B3LYP/6-31++g(d,p), HF/6-31++g(d,p) and M062X/6-31++g(d,p) levels. As the biological application of the synthesized compounds, (i) their inhibition properties of the synthesized compounds on Acetylcholinesterase (AChE) and Butyrylcholinesterase (BChE) metabolic enzymes were investigated, and their potential anticancer activities against neuroblastoma (NB; SH-SY5Y) and healthy fibroblast (NIH-3T3) cell lines were determined by in vitro assays. All compounds showed inhibition at nanomolar level with the Ki values in the range of 97.86 ± 30.51-516.82 ± 31.42 nM for AChE, 33.21 ± 4.45-78.50 ± 8.91 nM for BChE, respectively. It has been determined that all tested compounds have a remarkable cytotoxic effect against SH-SY5Y, and IC50 values were significantly lower than NIH-3T3 cells. The lowest IC50 value was observed in SB-Cl-OH (7.48 ± 0.86 µM) and SB-Cl-CN (7.31 ± 0.69 µM). The molecular docking of the molecules was also investigated using crystal structure of AChE enzyme protein (PDB ID: 4M0E), crystal structure of BChE protein (PDB ID: 6R6V) and SH-SY5Y cancer protein (PDB ID: 2F3F, 3PBL and 5WIV). The ADME properties of the compounds were investigated. MM/GBSA method is calculated binding free energy. Afterwards, ADME/T analysis was performed to examine the some properties of the molecules.Communicated by Ramaswamy H. Sarma.

Neuroblastoma Patients' Outcome and Chromosomal Instability

Chromosomal instability (CIN) induces a high rate of losses or gains of whole chromosomes or parts of chromosomes. It is a hallmark of most human cancers and one of the causes of aneuploidy and intra-tumor heterogeneity. The present study aimed to evaluate the potential prognostic role of CIN in NB patients at diagnosis. We performed array comparative genomic hybridization analyses on 451 primary NB patients at the onset of the disease. To assess global chromosomal instability with high precision, we focused on the total number of DNA breakpoints of gains or losses of chromosome arms. For each tumor, an array-CGH-based breakpoint instability index (BPI) was assigned which defined the total number of chromosomal breakpoints per genome. This approach allowed us to quantify CIN related to whole genome disruption in all NB cases analyzed. We found differences in chromosomal breakages among the NB clinical risk groups. High BPI values are negatively associated with survival of NB patients. This association remains significant when correcting for stage, age, and MYCN status in the Cox model. Stratified analysis confirms the prognostic effect of BPI index in low-risk NB patients with non-amplified MYCN and with segmental chromosome aberrations.

miR-124 and VAMP3 Act Antagonistically in Human Neuroblastoma

Neuroblastoma (NB) is the most common extracranial solid tumor that affects developing nerve cells in the fetus, infants, and children. miR-124 is a microRNA (miRNA) enriched in neuronal tissues, and VAMP3 (vesicle-associated membrane protein 3) has been reported to be an miR-124 target, although the relationship between NB and miR-124 or VAMP3 is unknown. Our current work identified that miR-124 levels are high in NB cases and that elevated miR-124 correlates with worse NB outcomes. Conversely, depressed VAMP3 correlates with worse NB outcomes. To investigate the mechanisms by which miR-124 and VAMP3 regulate NB, we altered miR-124 or VAMP3 expression in human NB cells and observed that increased miR-124 and reduced VAMP3 stimulated cell proliferation and suppressed apoptosis, while increased VAMP3 had the opposite effects. Genome-wide mRNA expression analyses identified gene and pathway changes which might explain the NB cell phenotypes. Together, our studies suggest that miR-124 and VAMP3 could be potential new markers of NB and targets of NB treatments.

Phenotyping neuroblastoma cells through intelligent scrutiny of stain-free biomarkers in holographic flow cytometry

To efficiently tackle certain tumor types, finding new biomarkers for rapid and complete phenotyping of cancer cells is highly demanded. This is especially the case for the most common pediatric solid tumor of the sympathetic nervous system, namely, neuroblastoma (NB). Liquid biopsy is in principle a very promising tool for this purpose, but usually enrichment and isolation of circulating tumor cells in such patients remain difficult due to the unavailability of universal NB cell-specific surface markers. Here, we show that rapid screening and phenotyping of NB cells through stain-free biomarkers supported by artificial intelligence is a viable route for liquid biopsy. We demonstrate the concept through a flow cytometry based on label-free holographic quantitative phase-contrast microscopy empowered by machine learning. In detail, we exploit a hierarchical decision scheme where at first level NB cells are classified from monocytes with 97.9% accuracy. Then we demonstrate that different phenotypes are discriminated within NB class. Indeed, for each cell classified as NB its belonging to one of four NB sub-populations (i.e., CHP212, SKNBE2, SHSY5Y, and SKNSH) is evaluated thus achieving accuracy in the range 73.6%-89.1%. The achieved results solve the realistic problem related to the identification circulating tumor cell, i.e., the possibility to recognize and detect tumor cells morphologically similar to blood cells, which is the core issue in liquid biopsy based on stain-free microscopy. The presented approach operates at lab-on-chip scale and emulates real-world scenarios, thus representing a future route for liquid biopsy by exploiting intelligent biomedical imaging.

Identification of the molecular subtypes and construction of risk models in neuroblastoma

The heterogeneity of neuroblastoma directly affects the prognosis of patients. Individualization of patient treatment to improve prognosis is a clinical challenge at this stage and the aim of this study is to characterize different patient populations. To achieve this, immune-related cell cycle genes, identified in the GSE45547 dataset using WGCNA, were used to classify cases from multiple datasets (GSE45547, GSE49710, GSE73517, GES120559, E-MTAB-8248, and TARGET) into subgroups by consensus clustering. ESTIMATES, CIBERSORT and ssGSEA were used to assess the immune status of the patients. And a 7-gene risk model was constructed based on differentially expressed genes between subtypes using randomForestSRC and LASSO. Enrichment analysis was used to demonstrate the biological characteristics between different groups. Key genes were screened using randomForest to construct neural network and validated. Finally, drug sensitivity was assessed in the GSCA and CellMiner databases. We classified the 1811 patients into two subtypes based on immune-related cell cycle genes. The two subtypes (Cluster1 and Cluster2) exhibited distinct clinical features, immune levels, chromosomal instability and prognosis. The same significant differences were demonstrated between the high-risk and low-risk groups. Through our analysis, we identified neuroblastoma subtypes with unique characteristics and established risk models which will improve our understanding of neuroblastoma heterogeneity.

Variant rs8400 enhances ALKBH5 expression through disrupting miR-186 binding and promotes neuroblastoma progression

Objective

AlkB homolog 5 (ALKBH5) has been proven to be closely related to tumors. However, the role and molecular mechanism of ALKBH5 in neuroblastomas have rarely been reported.

Methods

The potential functional single-nucleotide polymorphisms (SNPs) in ALKBH5 were identified by National Center for Biotechnology Information (NCBI) dbSNP screening and SNPinfo software. TaqMan probes were used for genotyping. A multiple logistic regression model was used to evaluate the effects of different SNP loci on the risk of neuroblastoma. The expression of ALKBH5 in neuroblastoma was evaluated by Western blotting and immunohistochemistry (IHC). Cell counting kit-8 (CCK-8), plate colony formation and 5-ethynyl-2'-deoxyuridine (EdU) incorporation assays were used to evaluate cell proliferation. Wound healing and Transwell assays were used to compare cell migration and invasion. Thermodynamic modelling was performed to predict the ability of miRNAs to bind to ALKBH5 with the rs8400 G/A polymorphism. RNA sequencing, N6-methyladenosine (m6A) sequencing, m6A methylated RNA immunoprecipitation (MeRIP) and a luciferase assay were used to identify the targeting effect of ALKBH5 on SPP1.

Results

ALKBH5 was highly expressed in neuroblastoma. Knocking down ALKBH5 inhibited the proliferation, migration and invasion of cancer cells. miR-186-3p negatively regulates the expression of ALKBH5, and this ability is affected by the rs8400 polymorphism. When the G nucleotide was mutated to A, the ability of miR-186-3p to bind to the 3'-UTR of ALKBH5 decreased, resulting in upregulation of ALKBH5. SPP1 is the downstream target gene of the ALKBH5 oncogene. Knocking down SPP1 partially restored the inhibitory effect of ALKBH5 downregulation on neuroblastoma. Downregulation of ALKBH5 can improve the therapeutic efficacy of carboplatin and etoposide in neuroblastoma.

Conclusions

We first found that the rs8400 G>A polymorphism in the m6A demethylase-encoding gene ALKBH5 increases neuroblastoma susceptibility and determines the related mechanisms. The aberrant regulation of ALKBH5 by miR-186-3p caused by this genetic variation in ALKBH5 promotes the occurrence and development of neuroblastoma through the ALKBH5-SPP1 axis.

Whole-exome sequencing reveals genetic variants in low-risk and high-risk neuroblastoma

This study aimed to investigate the genetic aberrations in neuroblastoma (NB) by comparing high and low-risk NB patients by whole-exome sequencing (WES) and to reveal the heterogeneity and association between somatic variants and clinical features. Seven NB patients with available clinical data were included in the study (4 in the low-risk group and 3 in the high-risk group). WES was performed and somatic variants associated with NB genes in the COSMIC database were selected through bioinformatics pipeline analysis. Variants were determined using the Integrative Genomics Viewer (IGV). Some gene variations were found in both groups, including variations in oncogene and tumor suppressor genes. In general, candidate gene variations were associated with chromatin remodeling complexes, the RAS pathway, cell proliferation, and DNA repair mechanism. Some variations in CSF1R, MSH6, PTPN11, SOX9, RET, TSC1, and DNMT1 genes were detected only in high-risk patients, while EP300, TET2, MYCN, PRDM1, and ARID2 gene variations were detected only in low-risk patients. When high-risk gene variants were compared with the cBioportal cancer genomic database, two common gene variants (ARID1A and NCOR2) were identified. However, when low-risk gene variants were compared with the cBioportal cancer genomic database, no common genes were found. GO/KEGG enrichment analysis was performed to find relevant biological processes and molecular pathways related to gene variants, which will help to decipher the molecular mechanisms of NB tumorigenesis and the phenotypic differences between high-risk and low-risk patients.

Association between GPC2 polymorphisms and neuroblastoma risk in Chinese children

BACKGROUND

The cell surface glycoprotein glypican 2 (GPC2) has been shown to increase susceptibility to neuroblastoma, which is the most common malignancy in children. However, associations between single nucleotide polymorphism(s) of GPC2 and neuroblastoma risk remain unclarified.

METHODS

We conducted a case-control study to investigate two GPC2 polymorphisms (rs1918353 G>A and rs7799441 C>T) in 473 healthy controls and 402 pediatric patients with neuroblastoma. Single nucleotide polymorphism (SNP) genotyping was conducted on the samples by the TaqMan technique, and the data were subsequently analyzed by the t test, chi-squared test, and logistic regression model. In addition, we further performed stratification analysis by age, sex, tumor site of origin, or clinical stage to control confounding factors.

RESULTS

According to the data of dominant models (GA/AA vs. GG: adjusted OR = 0.99, 95% CI = 0.76-1.29, p = 0.943; CT/TT vs. CC: adjusted OR = 0.91, 95% CI = 0.70-1.19, p = 0.498) or other comparisons, as well as the conjoint analysis (adjusted OR = 1.22, 95% CI = 0.93-1.59, p = 0.152), we unfortunately proved that the analysis of single or multiple loci did not support any significant association of GPC2 polymorphisms with susceptibility to neuroblastoma.

CONCLUSION

GPC2 polymorphisms (rs1918353 G>A and rs7799441 C>T) are unable to statistically affect neuroblastoma risk in Chinese children. Therefore, more samples, especially from patients of various ethnic backgrounds, are required to increase the sample size and verify the effect of GPC2 polymorphisms on neuroblastoma risk in the presence of ethnic factor.

Identification of a novel eighteen-gene signature of recurrent metastasis neuroblastoma

Neuroblastoma is the most common malignant tumor in childhood, and metastases occur in more than 30% patients. Recurrent metastasis is the main cause of poor prognosis and high mortality in neuroblastoma. In this regard, there is still a lack of sufficient biomarkers and effective therapies. Therefore, we performed a multi-omics analysis of neuroblastoma patients from Therapeutically Applicable Research To Generate Effective Treatments (TARGET). With clinical relapse site information, tumor samples derived from the primary site were divided into recurrent metastasis and primary tumor groups. The initial gene signature was obtained by comparing RNA-Seq and copy number variation differences. Survival data was used to further filter prognosis-related genes. This 18-gene signature consists of three clusters: tumor suppression, cell proliferation, and immunity. A super enhancer is involved in the enhanced expression of NCAPG in cluster2 together with IRF3. Based on the gene signature expression in primary neuroblastoma, it is possible to predict tumor metastasis before it occurs. According to the anticancer drug dataset of Genomics of Drug Sensitivity in Cancer (GDSC), vinorelbine and docetaxel were predicted to have high sensitivity against recurrent metastatic neuroblastoma. In conclusion, our study offers a novel metastasis biomarker and helps understand the mechanisms of tumor recurrent metastasis. KEY MESSAGES: We identified a novel eighteen-gene signature of recurrent metastasis neuroblastoma and build risk and classification models. We dissected the regulatory role of NCAPG in signatures. We found immune exhaustion and immunosuppression in recurrent metastasis neuroblastoma. Vinorelbine and docetaxel were predicted to have high sensitivity against recurrent metastatic neuroblastoma.

Therapy resistance in neuroblastoma: Mechanisms and reversal strategies

Neuroblastoma is one of the most common pediatric solid tumors that threaten the health of children, accounting for about 15% of childhood cancer-related mortality in the United States. Currently, multiple therapies have been developed and applied in clinic to treat neuroblastoma including chemotherapy, radiotherapy, targeted therapy, and immunotherapy. However, the resistance to therapies is inevitable following long-term treatment, leading to treatment failure and cancer relapse. Hence, to understand the mechanisms of therapy resistance and discover reversal strategies have become an urgent task. Recent studies have demonstrated numerous genetic alterations and dysfunctional pathways related to neuroblastoma resistance. These molecular signatures may be potential targets to combat refractory neuroblastoma. A number of novel interventions for neuroblastoma patients have been developed based on these targets. In this review, we focus on the complicated mechanisms of therapy resistance and the potential targets such as ATP-binding cassette transporters, long non-coding RNAs, microRNAs, autophagy, cancer stem cells, and extracellular vesicles. On this basis, we summarized recent studies on the reversal strategies to overcome therapy resistance of neuroblastoma such as targeting ATP-binding cassette transporters, MYCN gene, cancer stem cells, hypoxia, and autophagy. This review aims to provide novel insight in how to improve the therapy efficacy against resistant neuroblastoma, which may shed light on the future directions that would enhance the treatment outcomes and prolong the survival of patients with neuroblastoma.

Inherited rare variants in homologous recombination and neurodevelopmental genes are associated with increased risk of neuroblastoma

BACKGROUND

Neuroblastoma (NB) is the most common solid extracranial paediatric tumour. Genome-wide association studies have driven the discovery of common risk variants, but no large study has investigated the contribution of rare variants to NB susceptibility. Here, we conducted a whole-exome sequencing (WES) of 664 NB cases and 822 controls and used independent validation datasets to identify genes with rare risk variants and involved pathways.

METHODS

WES was performed at 50× depth and variants were jointly called in cases and controls. We developed two models to identify mutations with high clinical impact (P/LP model) and to discover less penetrant risk mutations affecting non-canonical cancer pathways (RPV model). We performed a gene-level collapsing test using Firth's logistic regression in 242 selected cancer predisposition genes (CPGs) and a gene-sets burden analysis of biologically-informed pathways.

FINDINGS

Twelve percent of patients carried P/LP variants in CPGs and showed a significant enrichment (P = 2.3 × 10^-4) compared to controls (6%). We identified P/LP variants in 45 CPGs enriched in homologous recombination (HR) pathway. The most P/LP enriched genes in NB were BRCA1, ALK and RAD51C. Additionally, we found higher RPV burden in gene-sets of neuron differentiation, neural tube development and synapse assembly, and in gene-sets associated with neurodevelopmental disorders (NDD).

INTERPRETATION

The high fraction of NB patients with P/LP variants indicates the need of genetic counselling. Furthermore, inherited rare variants predispose to NB development by affecting mechanisms related to HR and neurodevelopmental processes, and demonstrate that NDD genes are altered in NB at the germline level.

FUNDING

Associazione Italiana per la Ricerca sul Cancro, Fondazione Italiana per la Lotta al Neuroblastoma, Associazione Oncologia Pediatrica e Neuroblastoma, Regione Campania, Associazione Giulio Adelfio onlus, and Italian Health Ministry.

Italian Precision Medicine in Pediatric Oncology: Moving beyond Actionable Alterations

Neuroblastoma (NB) is the most common extracranial solid tumor encountered in childhood. Although there has been significant improvement in the outcomes of patients with high-risk disease, the prognosis for patients with metastatic relapse or refractory disease is poor. Hence, the clinical integration of genome sequencing into standard clinical practice is necessary in order to develop personalized therapy for children with relapsed or refractory disease. The PeRsonalizEdMEdicine (PREME) project focuses on the design of innovative therapeutic strategies for patients suffering from relapsed NB. We performed whole exome sequencing (WES) of patient-matched tumor-normal samples to identify genetic variants amenable to precision medicine. Specifically, two patients were studied (First case: a three-year-old male with early relapsed NB; Second case: a 20-year-old male who relapsed 10 years after the first diagnosis of NB). Results were reviewed by a multi-disciplinary molecular tumor board (MTB) and clinical reports were issued to the ordering physician. WES revealed the mutation c.G320C in the CUL4A gene in case 1 and the mutation c.A484G in the PSMC2 gene in case 2. Both patients were treated according to these actionable alterations, with promising results. The effective treatment of NB is one of the main challenges in pediatric oncology. In the era of precision medicine, the need to design new therapeutic strategies for NB is fundamental. Our results demonstrate the feasibility of incorporating clinical WES into pediatric oncology practice.

Whole exome sequencing of high-risk neuroblastoma identifies novel non-synonymous variants

Neuroblastoma (NBL), one of the main death-causing cancers in children, is known for its remarkable genetic heterogeneity and varied patient outcome spanning from spontaneous regression to widespread disease. Specific copy number variations and single gene rearrangements have been proven to be associated with biological behavior and prognosis; however, there is still an unmet need to enlarge the existing armamentarium of prognostic and therapeutic targets. We performed whole exome sequencing (WES) of samples from 18 primary tumors and six relapse samples originating from 18 NBL patients. Our cohort consists of 16 high-risk, one intermediate, and one very low risk patient. The obtained results confirmed known mutational hotspots in ALK and revealed other non-synonymous variants of NBL-related genes (TP53, DMD, ROS, LMO3, PRUNE2, ERBB3, and PHOX2B) and of genes cardinal for other cancers (KRAS, PIK3CA, and FLT3). Beyond, GOSeq analysis determined genes involved in biological adhesion, neurological cell-cell adhesion, JNK cascade, and immune response of cell surface signaling pathways. We were able to identify novel coding variants present in more than one patient in nine biologically relevant genes for NBL, including TMEM14B, TTN, FLG, RHBG, SHROOM3, UTRN, HLA-DRB1, OR6C68, and XIRP2. Our results may provide novel information about genes and signaling pathways relevant for the pathogenesis and clinical course in high-risk NBL.

Exploration of genetic ancestry and socioeconomic status in the incidence of neuroblastoma: An ecological study

Although global differences in the incidence of neuroblastoma have been examined, the underlying mechanism has yet to be elucidated. Previous studies have suggested genetic ancestry and human development index (HDI) as contributing factors, but few studies have been conducted at the international level. Here, we aimed to examine whether the frequency of common genomic variation associated with neuroblastoma can affect its risk at the ecological level with consideration of the HDI. Minor allele frequencies (MAFs) for 22 single-nucleotide polymorphisms (SNPs) were abstracted from the Geography of Genetic Variants Browser. The number of incident neuroblastomas for each population was obtained from the Cancer Incidence in Five Continents series. Further, population pseudo-polygenic risk scores (pp-PRSs) were calculated as a sum of MAFs at the population level, each of which was weighted by effect sizes from prior studies. Negative binomial regression was used to estimate the incidence rate ratios (IRRs) and the 95% confidence intervals (CIs) to examine whether differences in MAFs across the population influence the risk of neuroblastoma, with and without adjustment for HDI and whether pp-PRSs can be a predictor of the risk of neuroblastoma. Overall, our results indicated that the neuroblastoma risk associated with variation in SNP frequency could not be differentiated from that of HDI at the ecological level. Additionally, pp-PRSs were not significantly associated with the risk of neuroblastoma (IRR: 0.99, 95% CI: 0.62-1.60). Further study using individual-level data is warranted to minimize the bias related to the use of population-level data in this study.

CNV assessments associated with outcome distinctions for adult and pediatric cancers: Loss of BRCA1 in neuroblastoma associates with a lower survival probability

DNA copy number variations (CNV) are common in cancer development, however, CNV detection approaches that include assessments of small CNVs, for example, due to locally misaligned sister chromatid exchanges, have not been substantially applied. Using such approaches, CNVs have been detected, in the cancer setting, for regulatory elements common to both proliferation and apoptosis effector genes, but no linkage has yet been made to cancer patient clinical data. Thus, we hypothesized that copy number losses, including local copy number losses, of specific apoptosis effector genes would be associated with reduced survival. Both whole genome and whole exome files were processed for validations and consistency. Results indicated lower late-stage survival for multiple myeloma cases representing reduced BAD and CASP3 copies, as well as for lung adenocarcinoma cases representing reduced BAX and CASP3 copies. Results also indicated that neuroblastoma (NBL) cases representing reduced copies of CASP9 and BRCA1 had reduced overall survival probabilities, with the BRCA1 results being particularly notable due to previous reports of BRCA1 inactivating mutations in NBL. Overall, novel approaches to assessing CNVs offers the promise of establishing patient risk stratifications and of identifying single genes or other small spaces in the genome where a CNV may be linked to specific outcomes.

FGFR1 is a potential therapeutic target in neuroblastoma

BACKGROUND

FGFR1 regulates cell-cell adhesion and extracellular matrix architecture and acts as oncogene in several cancers. Potential cancer driver mutations of FGFR1 occur in neuroblastoma (NB), a neural crest-derived pediatric tumor arising in sympathetic nervous system, but so far they have not been studied experimentally. We investigated the driver-oncogene role of FGFR1 and the implication of N546K mutation in therapy-resistance in NB cells.

METHODS

Public datasets were used to predict the correlation of FGFR1 expression with NB clinical outcomes. Whole genome sequencing data of 19 paired diagnostic and relapse NB samples were used to find somatic mutations. In NB cell lines, silencing by short hairpin RNA and transient overexpression of FGFR1 were performed to evaluate the effect of the identified mutation by cell growth, invasion and cologenicity assays. HEK293, SHSY5Y and SKNBE2 were selected to investigate subcellular wild-type and mutated protein localization. FGFR1 inhibitor (AZD4547), alone or in combination with PI3K inhibitor (GDC0941), was used to rescue malignant phenotypes induced by overexpression of FGFR1 wild-type and mutated protein.

RESULTS

High FGFR1 expression correlated with low relapse-free survival in two independent NB gene expression datasets. In addition, we found the somatic mutation N546K, the most recurrent point mutation of FGFR1 in all cancers and already reported in NB, in one out of 19 matched primary and recurrent tumors. Loss of FGFR1 function attenuated invasion and cologenicity in NB cells, whereas FGFR1 overexpression enhanced oncogenicity. The overexpression of FGFR1^N546K protein showed a higher nuclear localization compared to wild-type protein and increased cellular invasion and cologenicity. Moreover, N546K mutation caused the failure in response to treatment with FGFR1 inhibitor by activation of ERK, STAT3 and AKT pathways. The combination of FGFR1 and PI3K pathway inhibitors was effective in reducing the invasive and colonigenic ability of cells overexpressing FGFR1 mutated protein.

CONCLUSIONS

FGFR1 is an actionable driver oncogene in NB and a promising therapy may consist in targeting FGFR1 mutations in patients with therapy-resistant NB.

Osteogenesis Imperfecta/Ehlers-Danlos Overlap Syndrome and Neuroblastoma-Case Report and Review of Literature

Osteogenesis imperfecta/Ehlers−Danlos (OI/EDS) overlap syndrome is a recently described disorder of connective tissue, characterized by mutation of COL1A1 (17q21.33) or COL1A2 (7q21.3) genes, that are involved in α-1 and α-2 chains of type 1 collagen synthesis. The clinical spectrum of this new clinical entity is broad: patients could present a mixed phenotype that includes features of both osteogenesis imperfecta (bone fragility, long bone fractures, blue sclerae, short stature) and Ehlers−Danlos syndrome (joint hyperextensibility, soft and hyperextensible skin, abnormal wound healing, easy bruising, vascular fragility). We reported the case of a young Caucasian girl with severe short stature and a previous history of neuroblastoma, who displayed the compound phenotype of OI/EDS. Next generation sequencing was applied to the proband and her parent genome. Our patient presented a de novo heterozygous COL1A1 variant (c.3235G>A, p.Gly1079Ser), whose presence might be indicative of diagnosis of OI/EDS overlap syndrome. We also hypothesize that the association with the previous history of neuroblastoma could be influenced by the presence of COL1A1 mutation, whose role has been already described in the behavior and progression of some cancers.

Neuroblastoma-associated Renal Cell Carcinoma: A Case Report and Review of the Literature

Neuroblastoma-associated renal cell carcinoma (RCC) is a very rare subtype of renal neoplasia and only a handful of cases have been reported. Here we present a 15-year-old boy with metastatic RCC with a previous history of advanced stage neuroblastoma and germline mutation in the TP53 tumor suppressor gene. The probability of the RCC and indeed, the neuroblastoma itself being related to a cancer predisposition syndrome rather than a therapy induced second malignancy, is discussed.

Somatic mutations enriched in cis-regulatory elements affect genes involved in embryonic development and immune system response in neuroblastoma

Noncoding cis-regulatory variants have gained interest as cancer drivers, yet progress in understanding their significance is hindered by the numerous challenges and limitations of variant prioritization. To overcome these limitations, we focused on active cis-regulatory elements (aCRE) in order to design a customized panel for the deep sequencing of 56 neuroblastoma tumor and normal DNA sample pairs. In order to search for driver mutations, aCREs were defined by reanalysis of H3K27ac ChiP-seq peaks in 25 neuroblastoma cell lines. These regulatory genomic regions were tested for an excess of somatic mutations and assessed for statistical significance using a global approach that accounted for chromatin accessibility and replication timing. Additional validation was provided by whole genome sequence analysis of 151 neuroblastomas. Analysis of Hi-C data determined the presence of candidate target genes interacting with mutated regions. An excess of somatic mutations in aCREs of diverse genes were identified, including IPO7, HAND2, and ARID3A. CRISPR-Cas9 editing was utilized to assess the functional consequences of mutations in the IPO7 aCRE. Patients with noncoding mutations in aCREs showed inferior overall and event-free survival independent of age at diagnosis, stage, risk stratification, and MYCN status. Expression of aCRE-interacting genes correlated strongly with negative prognostic markers and low survival rates. Moreover, a convergence between the biological functions of aCRE target genes and transcription factors with mutated binding motifs was associated with embryonic development and immune system response. Overall, this strategy enabled the identification of somatic mutations in regulatory elements that collectively promote neuroblastoma tumorigenesis.

Single-cell transcriptomics of neuroblastoma identifies chemoresistance-associated genes and pathways

High-Risk neuroblastoma (NB) survival rate is still <50%, despite treatments being more and more aggressive. The biggest hurdle liable to cancer therapy failure is the drug resistance by tumor cells that is likely due to the intra-tumor heterogeneity (ITH). To investigate the link between ITH and therapy resistance in NB, we performed a single cell RNA sequencing (scRNAseq) of etoposide and cisplatin resistant NB and their parental cells. Our analysis showed a clear separation of resistant and parental cells for both conditions by identifying 8 distinct tumor clusters in etoposide-resistant/parental and 7 in cisplatin-resistant/parental cells. We discovered that drug resistance can affect NB cell identities; highlighting the bi-directional ability of adrenergic-to-mesenchymal transition of NB cells. The biological processes driving the identified resistant cell subpopulations revealed genes such as (BARD1, BRCA1, PARP1, HISTH1 axis, members of RPL family), suggesting a potential drug resistance due to the acquisition of DNA repair mechanisms and to the modification of the drug targets. Deconvolution analysis of bulk RNAseq data from 498 tumors with cell subpopulation signatures showed that the transcriptional heterogeneity of our cellular models reflected the ITH of NB tumors and allowed the identification of clusters associated with worse/better survival.

Our study demonstrates the distinct cell populations characterized by genes involved in different biological processes can have a role in NB drug treatment failure. These findings evidence the importance of ITH in NB drug resistance studies and the chance that scRNA-seq analysis offers in the identification of genes and pathways liable for drug resistance.

YTHDC1 gene polymorphisms and neuroblastoma susceptibility in Chinese children

Neuroblastoma (NB) is the most common extracranial tumor in children. YTHDC1, a member of RNA methylation modification binding proteins, plays critical roles in tumor occurrence and metastasis. However, it is unclear whether YTHDC1 gene polymorphisms are related to NB susceptibility. Herein, we aimed to evaluate the association between YTHDC1 gene polymorphisms (rs2293596 T>C, rs2293595 T>C, rs3813832 T>C) and susceptibility of NB by logistic regression models. In this eight-center case-control study, 898 patients with NB and 1734 healthy controls were genotyped by TaqMan assay. The results showed that rs3813832 TC genotype could significantly reduce the susceptibility of NB compared with the TT genotype [adjusted odds ratio (AOR) = 0.81, 95% confidence interval (CI) = 0.68-0.96, P = 0.018]. Combined genotype analysis revealed that individuals with 3 protective genotypes had a prominently lower NB risk than those with 0-2 protective genotypes (AOR = 0.80, 95% CI = 0.68-0.94, P = 0.006). The stratified analysis also demonstrated the protective effect of rs3813832 TC/CC and 3 protective genotypes in certain subgroups. Further functional experiments revealed that YTHDC1 siRNA-554, targeting the area near the rs3813832 T>C polymorphism site, could observably inhibit the proliferation and migration of NB cells. In conclusion, our findings highlight the involvement of YTHDC1 gene and its genetic variants in the etiology of NB.

The fellowship of the RING: BRCA1, its partner BARD1 and their liaison in DNA repair and cancer

The breast cancer type 1 susceptibility protein (BRCA1) and its partner - the BRCA1-associated RING domain protein 1 (BARD1) - are key players in a plethora of fundamental biological functions including, among others, DNA repair, replication fork protection, cell cycle progression, telomere maintenance, chromatin remodeling, apoptosis and tumor suppression. However, mutations in their encoding genes transform them into dangerous threats, and substantially increase the risk of developing cancer and other malignancies during the lifetime of the affected individuals. Understanding how BRCA1 and BARD1 perform their biological activities therefore not only provides a powerful mean to prevent such fatal occurrences but can also pave the way to the development of new targeted therapeutics. Thus, through this review work we aim at presenting the major efforts focused on the functional characterization and structural insights of BRCA1 and BARD1, per se and in combination with all their principal mediators and regulators, and on the multifaceted roles these proteins play in the maintenance of human genome integrity.

The Role of Biopsy in the Workup of Patients with Neuroblastoma: Comparison of the Incidence of Surgical Complications and the Diagnostic Reliability of Diverse Techniques

Neuroblastoma (NB) is the most common extracranial solid tumor in childhood, accounting for approximately 15% of all cancer-related deaths in the pediatric population. The overall survival of children with high-risk disease is around 40-50% despite the aggressive treatment protocols. In accordance with the most recent guidelines, a complete classification of the primary tumor, including its histopathological and molecular analysis, is necessary. In this regard, the biopsy of the primary tumor is an important diagnostic procedure adopted not only to confirm the diagnosis but also for staging and risk stratification of the disease. In this study, the authors describe their unicentric experience with four different approaches adopted for sampling NB tumors: (i) the open incisional biopsy; (ii) the minimally invasive thoracoscopic/laparoscopic incisional biopsy; (iii) the ultrasound-guided core needle biopsy; (iv) the laparoscopic-assisted core needle biopsy. The benefits of each technique are analyzed along with their contraindications.

A review of the biological and clinical implications of RAS-MAPK pathway alterations in neuroblastoma

Neuroblastoma is the most common extra-cranial solid tumor in children, representing approximately 8% of all malignant childhood tumors and 15% of pediatric cancer-related deaths. Recent sequencing and transcriptomics studies have demonstrated the RAS-MAPK pathway’s contribution to the development and progression of neuroblastoma. This review compiles up-to-date evidence of this pathway’s involvement in neuroblastoma. We discuss the RAS-MAPK pathway’s general functioning, the clinical implications of its deregulation in neuroblastoma, and current promising therapeutics targeting proteins involved in signaling.

Personalized Medicine for Neuroblastoma: Moving from Static Genotypes to Dynamic Simulations of Drug Response

High-risk neuroblastoma is an aggressive childhood cancer that is characterized by high rates of chemoresistance and frequent metastatic relapse. A number of studies have characterized the genetic and epigenetic landscape of neuroblastoma, but due to a generally low mutational burden and paucity of actionable mutations, there are few options for applying a comprehensive personalized medicine approach through the use of targeted therapies. Therefore, the use of multi-agent chemotherapy remains the current standard of care for neuroblastoma, which also conceptually limits the opportunities for developing an effective and widely applicable personalized medicine approach for this disease. However, in this review we outline potential approaches for tailoring the use of chemotherapy agents to the specific molecular characteristics of individual tumours by performing patient-specific simulations of drug-induced apoptotic signalling. By incorporating multiple layers of information about tumour-specific aberrations, including expression as well as mutation data, these models have the potential to rationalize the selection of chemotherapeutics contained within multi-agent treatment regimens and ensure the optimum response is achieved for each individual patient.

USP24 Is a Cancer-Associated Ubiquitin Hydrolase, Novel Tumor Suppressor, and Chromosome Instability Gene Deleted in Neuroblastoma

Deubiquitinating enzymes are increasingly recognized to play important roles in cancer, with many acting as oncogenes or tumor suppressors. In this study, we employed a bioinformatics approach to screen for enzymes from this family involved in cancer and found USP24 as a potent predictor of poor outcomes in neuroblastoma, an aggressive childhood cancer. USP24 resides in a region commonly deleted in neuroblastoma, yet was independently associated with poor outcomes in this disease. Deletion of Usp24 in a murine model resulted in degradation of collapsin response mediator protein 2 (CRMP2), a regulator of axon growth, guidance, and neuronal polarity. Cells lacking USP24 had significant increases in spindle defects, chromosome missegregation, and aneuploidy, phenotypes that were rescued by the restoration of CRMP2. USP24 prevented aneuploidy by maintaining spindle-associated CRMP2, which is required for mitotic accuracy. Our findings further indicate that USP24 is a tumor suppressor that may play an important role in the pathogenesis of neuroblastoma. SIGNIFICANCE: This study identifies the chromosome instability gene USP24 as frequently deleted in neuroblastoma and provides important insight into the pathogenesis of this aggressive childhood cancer.

Neuroblastoma and the epigenome

Neuroblastoma (NB) is a pediatric cancer of the sympathetic nervous system and one of the most common solid tumors in infancy. Amplification of MYCN, copy number alterations, numerical and segmental chromosomal aberrations, mutations, and rearrangements on a handful of genes, such as ALK, ATRX, TP53, RAS/MAPK pathway genes, and TERT, are attributed as underlying causes that give rise to NB. However, the heterogeneous nature of the disease-along with the relative paucity of recurrent somatic mutations-reinforces the need to understand the interplay of genetic factors and epigenetic alterations in the context of NB. Epigenetic mechanisms tightly control gene expression, embryogenesis, imprinting, chromosomal stability, and tumorigenesis, thereby playing a pivotal role in physio- and pathological settings. The main epigenetic alterations include aberrant DNA methylation, disrupted patterns of posttranslational histone modifications, alterations in chromatin composition and/or architecture, and aberrant expression of non-coding RNAs. DNA methylation and demethylation are mediated by DNA methyltransferases (DNMTs) and ten-eleven translocation (TET) proteins, respectively, while histone modifications are coordinated by histone acetyltransferases and deacetylases (HATs, HDACs), and histone methyltransferases and demethylases (HMTs, HDMs). This article focuses predominately on the crosstalk between the epigenome and NB, and the implications it has on disease diagnosis and treatment.

Aminoacylase 1 (ACY-1) Mediates the Proliferation and Migration of Neuroblastoma Cells in Humans Through the ERK/Transforming Growth Factor β (TGF-β) Signaling Pathways

BACKGROUND Aminoacylase 1 (ACY-1) is a cytosolic enzyme that catalyzes amino acid deacylation and has been reported to participate in various human diseases. However, the role and mechanism of ACY-1 in neuroblastoma (NB) are not completely understood. The aim of this study was to elucidate the role of ACY-1 in NB. MATERIAL AND METHODS Overexpression and knockdown of ACY-1 in human NB cells were performed, and the transfection efficiency was assessed through fluorescence microscopy, real-time PCR, and western blotting. The effect of ACY-1 on tumorigenesis and metastasis was determined by cell counting, colony formation, wound healing, flow cytometry, and transwell invasion assays in vitro, and the signaling pathway was examined using western blotting. RESULTS ACY-1 overexpression inhibited proliferation and induced apoptosis in human NB cells. ACY-1 inhibited the colony formation ability, migration, and invasion of SH-SY5Y cell lines. Moreover, the ERK1/2 and TGF-ß1 signaling pathways were more active when ACY-1 was overexpressed in NB cells. However, the knockdown of ACY-1 in SH-SY5Y cell lines showed the opposite effects. CONCLUSIONS ACY-1 regulates the proliferation, migration, and invasion of human NB cells through the ERK1/2 and TGF-ß1 signaling pathways, implying that ACY-1 may serve as a therapeutic target for patients with NB.

YTHDF2 Gene rs3738067 A>G Polymorphism Decreases Neuroblastoma Risk in Chinese Children: Evidence From an Eight-Center Case-Control Study

Neuroblastoma is a primary malignancy mainly occurring in children. We have reported that polymorphisms of several N6-methyladenosine (m6A) RNA modification-related genes contributed to neuroblastoma risk in previous studies. YTHDF2, a "reader" of RNA m6A modification, is involved in cancer progression. Here, we estimated the association between a YTHDF2 gene rs3738067 A>G polymorphism and neuroblastoma susceptibility in 898 neuroblastoma patients and 1,734 healthy individuals from China. We found that the rs3738067 A>G could decrease neuroblastoma risk [AG vs. AA: adjusted odds ratio (OR) = 0.76, 95% confidence interval (CI) = 0.64-0.90, P = 0.002; AG/GG vs. AA: adjusted OR = 0.81, 95% CI = 0.69-0.95, P = 0.011). Besides, the rs3738067 AG/GG genotype was related to reduced neuroblastoma risk in the following subgroups: children aged 18 months and under, boys, patients with tumors originating from retroperitoneal, patients at clinical stage IV, and cases at clinical stages III plus IV. Importantly, false-positive report probability analysis proved our significant results worthy of close attention of. The expression quantitative trait locus analysis results revealed that the rs3738067 was associated with the expression of YTHDF2.

A Targeted Gene Panel for Circulating Tumor DNA Sequencing in Neuroblastoma

Background

Liquid biopsies do not reflect the complete mutation profile of the tumor but have the potential to identify actionable mutations when tumor biopsies are not available as well as variants with low allele frequency. Most retrospective studies conducted in small cohorts of pediatric cancers have illustrated that the technology yield substantial potential in neuroblastoma.

Aim

The molecular landscape of neuroblastoma harbors potentially actionable genomic alterations. We aimed to study the utility of liquid biopsy to characterize the mutational landscape of primary neuroblastoma using a custom gene panel for ctDNA targeted sequencing.

Methods

Targeted next-generation sequencing (NGS) was performed on ctDNA of 11 patients with primary neuroblastoma stage 4. To avoid the detection of false variants, we used UMIs (unique molecular identifiers) for the library construction, increased the sequencing depth and developed ad hoc bioinformatic analyses including the hard filtering of the variant calls.

Results

We identified 9/11 (81.8%) patients who carry at least one pathogenic variation. The most frequently mutated genes were KMT2C (five cases), NOTCH1/2 (four cases), CREBBP (three cases), ARID1A/B (three cases), ALK (two cases), FGFR1 (two cases), FAT4 (two cases) and CARD11 (two cases).

Conclusions

We developed a targeted NGS approach to identify tumor-specific alterations in ctDNA of neuroblastoma patients. Our results show the reliability of our approach to generate genomic information which can be integrated with clinical and pathological data at diagnosis.

Targeting MDM2 for Neuroblastoma Therapy: In Vitro and In Vivo Anticancer Activity and Mechanism of Action

Simple Summary

Neuroblastoma is a malignant tumor of the sympathetic nervous system that causes aggressive disease in children. The overall survival rate of high-risk patients is very low, therefore developing effective and safe therapies for neuroblastoma is an urgent unmet medical need. The mouse double minute 2 (MDM2) homolog gene is amplified and overexpressed in neuroblastoma and contributes to the poor response to treatment and poor prognosis in patients with high-risk neuroblastoma. Therefore, targeting MDM2 provides a promising approach to neuroblastoma therapy, especially for advanced disease. In the present study, we tested a unique MDM2 inhibitor, SP141, for its therapeutic efficacy and safety in neuroblastoma tumor models. We found that SP141 has significant anti- neuroblastoma activity in cell culture and inhibits tumor growth in animal models of human neuroblastoma, without any noticeable host toxicity. These results provide the basis for targeting MDM2 to treat high-risk neuroblastoma.

Abstract

Background: Neuroblastoma is an aggressive pediatric solid tumor with an overall survival rate of <50% for patients with high-risk disease. The majority (>98%) of pathologically-diagnosed neuroblastomas have wild-type p53 with intact functional activity. However, the mouse double minute 2 (MDM2) homolog, an E3 ubiquitin ligase, is overexpressed in neuroblastoma and leads to inhibition of p53. MDM2 also exerts p53-independent oncogenic functions. Thus, MDM2 seems to be an attractive target for the reactivation of p53 and attenuation of oncogenic activity in neuroblastoma. Methods: In this study, we evaluated the anticancer activities and underlying mechanisms of action of SP141, a first-in-class MDM2 inhibitor, in neuroblastoma cell lines with different p53 backgrounds. The findings were confirmed in mouse xenograft models of neuroblastoma. Results: We demonstrate that SP141 reduces neuroblastoma cell viability, induces apoptosis, arrests cells at the G2/M phase, and prevents cell migration, independent of p53. In addition, in neuroblastoma xenograft models, SP141 inhibited MDM2 expression and suppressed tumor growth without any host toxicity at the effective dose. Conclusions: MDM2 inhibition by SP141 results in the inhibition of neuroblastoma growth and metastasis, regardless of the p53 status of the cells and tumors. These findings provide proof-of-concept that SP141 represents a novel treatment option for both p53 wild-type and p53 null neuroblastoma.

Identification of novel prognostic markers of survival time in high-risk neuroblastoma using gene expression profiles

Neuroblastoma is the most common extracranial solid tumor in childhood. Patients in high-risk group often have poor outcomes with low survival rates despite several treatment options. This study aimed to identify a genetic signature from gene expression profiles that can serve as prognostic indicators of survival time in patients of high-risk neuroblastoma, and that could be potential therapeutic targets. RNA-seq count data was downloaded from UCSC Xena browser and samples grouped into Short Survival (SS) and Long Survival (LS) groups. Differential gene expression (DGE) analysis, enrichment analyses, regulatory network analysis and machine learning (ML) prediction of survival group were performed. Forty differentially expressed genes (DEGs) were identified including genes involved in molecular function activities essential for tumor proliferation. DEGs used as features for prediction of survival groups included EVX2, NHLH2, PRSS12, POU6F2, HOXD10, MAPK15, RTL1, LGR5, CYP17A1, OR10AB1P, MYH14, LRRTM3, GRIN3A, HS3ST5, CRYAB and NXPH3. An accuracy score of 82% was obtained by the ML classification models. SMIM28 was revealed to possibly have a role in tumor proliferation and aggressiveness. Our results indicate that these DEGs can serve as prognostic indicators of survival in high-risk neuroblastoma patients and will assist clinicians in making better therapeutic and patient management decisions.

Molecular targeting therapies for neuroblastoma: Progress and challenges

There is an urgent need to identify novel therapies for childhood cancers. Neuroblastoma is the most common pediatric solid tumor, and accounts for ~15% of childhood cancer‐related mortality. Neuroblastomas exhibit genetic, morphological and clinical heterogeneity, which limits the efficacy of existing treatment modalities. Gaining detailed knowledge of the molecular signatures and genetic variations involved in the pathogenesis of neuroblastoma is necessary to develop safer and more effective treatments for this devastating disease. Recent studies with advanced high‐throughput “omics” techniques have revealed numerous genetic/genomic alterations and dysfunctional pathways that drive the onset, growth, progression, and resistance of neuroblastoma to therapy. A variety of molecular signatures are being evaluated to better understand the disease, with many of them being used as targets to develop new treatments for neuroblastoma patients. In this review, we have summarized the contemporary understanding of the molecular pathways and genetic aberrations, such as those in MYCN, BIRC5, PHOX2B, and LIN28B, involved in the pathogenesis of neuroblastoma, and provide a comprehensive overview of the molecular targeted therapies under preclinical and clinical investigations, particularly those targeting ALK signaling, MDM2, PI3K/Akt/mTOR and RAS‐MAPK pathways, as well as epigenetic regulators. We also give insights on the use of combination therapies involving novel agents that target various pathways. Further, we discuss the future directions that would help identify novel targets and therapeutics and improve the currently available therapies, enhancing the treatment outcomes and survival of patients with neuroblastoma.

Congenital Neuroblastoma

Neuroblastoma is the most common extracranial solid tumor diagnosed during childhood and gives rise to various heterogeneous tumors along the sympathoadrenal axis. Congenital neuroblastoma accounts for 5% of total neuroblastoma cases diagnosed annually, with the majority of cases diagnosed in the first month after birth. Interestingly, neonates demonstrate a unique disease trajectory compared with children older than 1 year of age. This article will provide information on the pathogenesis and variable clinical presentation of congenital neuroblastoma, along with the biological prognostic factors that predict long-term outcomes in affected neonates.