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Whereas neuroblastoma (NB) with MYCN amplification presents a poor prognosis, no single marker allows to reliably predict outcome in tumours without MYCN amplification. We report here an extensive analysis of 147 NB samples at diagnosis, without MYCN amplification, by chromosomal comparative genomic hybridisation (CGH), providing a comprehensive overview of their genomic imbalances. Comparative genomic hybridisation profiles showed gains or losses of entire chromosomes (type 1) in 71 cases, whereas partial chromosome gains or losses (type 2), including gain involving 17q were observed in 68 cases. Atypical profiles were present in eight cases. A type 1 profile was observed more frequently in localised disease (P<0.0001), and in patients of less than 12 months at diagnosis (P<0.0001). A type 2 genomic profile was associated with a higher risk of relapse in the overall population (log-rank test; P<0.0001), but also in the subgroup of patients with localised disease (log-rank test, P=0.007). In multivariate analysis, the genomic profile was the strongest independent prognostic factor. In conclusion, the genomic profile is of prognostic impact in patients without MYCN amplification, making it a help in the management of low-stage NB. Further studies using higher-resolution CGH are needed to better characterise atypical genomic alterations. [ABSTRACT FROM AUTHOR]

Wilms tumor, or nephroblastoma, is themost frequent renal tumor of childhood, occuring mainly between 1 to 5 years of age, with a peak incidence around age 3 1/2. It most often occurs sporadically, but can also be observed in association with certain malformations, or in the context of predisposition syndromes such as the WAGR (Wilms tumor, Aniridia, Genito-urinary abnormalities, mental Retardation) or the Beckwith-Wiedemann syndrome, for which regular ultrasound screenings are justified. Wilms tumor is an embryonic tumor with variable histological features, characterized by an epithelial, a stromal and a blastemal component. Some histological subtypes have been associated with a better or poorer prognosis. Histological data at the time of diagnosis is currently mandatory only in an atypical clinical or radiological setting. In Europe, the SIOP protocols are based on preoperative therapy in order to decrease the risk of peroperative tumor rupture, and in order to increase the percentage of stage I tumors. Postoperative treatment depends on the local and metastatic stage as well as on the histological subtype. It consists of postoperative chemotherapy in nearly all cases, as well as, in some cases, external irradiation. New biological markers are needed in order to better identify tumors at risk of relapse and to define new potential therapeutic targets. [ABSTRACT FROM AUTHOR]

Background: Neuroblastoma (NB), a prevalent extracranial solid tumor in children, stems from the neural crest. Omics technologies are extensively employed in NB, and We analyzed published articles on NB omics to understand the research trends and hot topics in NB omics. Method: We collected all articles related to NB omics published from 2005 to 2023 from the Web of Science Core Collection database. Subsequently, we conducted analyses using VOSviewer, CiteSpace, Bibliometrix, and the Bibliometric online analysis platform (https://bibliometric.com/). Results: We included a total of 514 articles in our analysis. The increasing number of publications in this field since 2020 indicates growing attention to NB omics, gradually entering a mature development stage. These articles span 50 countries and 1,000 institutions, involving 3,669 authors and 292 journals. The United States has the highest publication output and collaboration with other countries, with Germany being the most frequent collaborator. Capital Medical University and the German Cancer Research Center are the institutions with the highest publication count. The Journal of Proteome Research and the Journal of Biological Chemistry are the most prolific journal and most co-cited journal, respectively. Wang, W, and Maris, JM are the scholars with the highest publication count and co-citations in this field. "Neuroblastoma" and "Expression" are the most frequent keywords, while "classification," "Metabolism," "Cancer," and "Diagnosis" are recent key terms. The article titled "Neuroblastoma" by John M. Maris is the most cited reference in this analysis. Conclusion: The continuous growth in NB omics research underscores its increasing significance in the scientific community. Omics technologies have facilitated the identification of potential biomarkers, advancements in personalized medicine, and the development of novel therapeutic strategies. Despite these advancements, the field faces significant challenges, including tumor heterogeneity, data standardization issues, and the translation of research findings into clinical practice. [ABSTRACT FROM AUTHOR]

Neuroblastoma, the deadliest solid tumor in children, exhibits alarming mortality rates, particularly among high-risk cases. To enhance survival rates, a more precise risk stratification for patients is imperative. Utilizing proteomic data from 34 cases with or without N-Myc amplification, we identified 28 differentially expressed ubiquitination-related proteins (URGs). From these, a prognostic signature comprising 6 URGs was constructed. A nomogram incorporating clinical-pathological parameters yielded impressive AUC values of 0.88, 0.93, and 0.95 at 1, 3, and 5 years, respectively. Functional experiments targeting the E3 ubiquitin ligase FBXO42, a component of the prognostic signature, revealed its TP53-dependent promotion of neuroblastoma cell proliferation. In conclusion, our ubiquitination-related prognostic model robustly predicts patient outcomes, guiding clinical decisions. Additionally, the newfound pro-proliferative role of FBXO42 offers a novel foundation for understanding the molecular mechanisms of neuroblastoma. [ABSTRACT FROM AUTHOR]

Simple Summary: Large datasets concerning childhood cancers are rare. Therefore, it is important to fully exploit all available data, which are distributed over several resources, including biomaterials, images, clinical trials, and registries. With privacy-preserving record linkage (PPRL), datasets can be merged, without disclosing the patients' identities. Although PPRL is already implemented or described in various settings, use case descriptions are fragmented and incomplete. The present paper gives an overview of current and future use cases of PPRL in childhood cancer. We screened the literature, projects, and trial protocols, analysed a hypothetical patient journey, and discussed use cases with experts. All the identified use cases were structured along six key dimensions. We conclude that PPRL is a key concept in childhood cancer. Therefore, PPRL strategies should already be considered when starting research projects, to avoid distributed data silos, to maximise the knowledge derived from collected data, and, ultimately, to improve outcomes for children with cancer. Large datasets in paediatric oncology are inherently rare. Therefore, it is paramount to fully exploit all available data, which are distributed over several resources, including biomaterials, images, clinical trials, and registries. With privacy-preserving record linkage (PPRL), personalised or pseudonymised datasets can be merged, without disclosing the patients' identities. Although PPRL is implemented in various settings, use case descriptions are currently fragmented and incomplete. The present paper provides a comprehensive overview of current and future use cases for PPRL in paediatric oncology. We analysed the literature, projects, and trial protocols, identified use cases along a hypothetical patient journey, and discussed use cases with paediatric oncology experts. To structure PPRL use cases, we defined six key dimensions: distributed personalised records, pseudonymisation, distributed pseudonymised records, record linkage, linked data, and data analysis. Selected use cases were described (a) per dimension and (b) on a multi-dimensional level. While focusing on paediatric oncology, most aspects are also applicable to other (particularly rare) diseases. We conclude that PPRL is a key concept in paediatric oncology. Therefore, PPRL strategies should already be considered when starting research projects, to avoid distributed data silos, to maximise the knowledge derived from collected data, and, ultimately, to improve outcomes for children with cancer. [ABSTRACT FROM AUTHOR]

Purpose: Neuroblastoma, the most common extracranial solid tumor in children under 5 years, often surrounds visceral arteries. This study aimed to analyze the working space provided by standardized surgical techniques at key arterial landmarks in adult cadavers. Methods: We assessed in eight adult cadavers the mobilization of the left colon, spleen and pancreas, right colon, duodenum and mesenteric root, access to the bursa omentalis. The average working space score (AWSS) was evaluated at the left and right renal artery, left and right side of the coeliac trunk, superior mesenteric and common hepatic artery. The score was defined as: (0) vessel not visible, (1) working space at the vessel ≤ 1x diameter of the aorta, (2) < 3x the diameter of the aorta, (3) ≥ 3x diameter of the aorta. Results: The maximum AWSS of 3 was achieved at key vascular landmarks through specific mobilization techniques. Conclusion: Additional mobilization of spleen, pancreas and mesenteric root and access to the bursa omentalis increase surgical working space at major visceral arteries. The results of our investigation provide surgeons with a useful guide to prepare for abdominal neuroblastoma resection. [ABSTRACT FROM AUTHOR]

Background: Although clear cell sarcoma of kidney (CCSK) is rare, it is the second most common renal tumor in children after Wilms' tumor. NWTS and SIOP are two major groups which had made tremendous efforts on renal tumors, but the strategies are different, for NWTS follows the upfront surgery principle providing definite pathology and the SIOP follows the upfront chemotherapy principle, each has its own advantages. Here we aimed to evaluate the outcomes of CCSK in China following NWTS strategies to analyze the prognostic factors. Methods: For this multicenter retrospective study, a total of 54 patients were enrolled from three children's hospitals, between April 2003 and December 2021. Treatment comprised upfront radical nephrectomy, followed by radiotherapy and intensive chemotherapy. Clinical records were regularly updated. Prognostic factors and survival rates were evaluated. Results: The 54 enrolled patients had a median age of 37 months (range, 4 months to 11.4 years). The stage distribution was 16% stage I (n = 9), 30% stage II (n = 16), 39% stage III (n = 21), and 15% stage IV (n = 8). Among stage IV, metastasis sites included the lung (n = 6), bone (n = 1), and intra-orbital/cervical lymph node (n = 1). After a median follow-up of 5.6 years, the 5-year event-free survival (EFS) was 82.4±5.4%, and overall survival was 88.1±4.6%. The EFS was 100% for stage I, 93.8 ±6.1% for stage II, 71.1±10.0% for stage III, and 68.6±18.6% for stage IV. Univariate analysis revealed that staging (III/IV), tumor rupture, and inferior vena cava tumor thrombus were inferior prognostic factors. Multivariate analysis revealed that tumor rupture was independent poor prognostic factor (P = 0.01, HR 5.9). Among relapsed patients, relapse occurred a median of 11 months after diagnosis (range, 4–41 months), and 50% (4/8) achieved a second complete remission after multiple treatment. None of the six lung metastasis patients received lung RT, only one patient developed a relapse and was salvaged by RT after relapse. Conclusions: Tumor rupture was independent poor prognostic factor. Upfront surgery of NWTS strategies can make a definite pathology diagnosis, but how to reduce tumor rupture during surgery is important especially in developing countries. The outcomes of patients with stage I–III CCSK in China were comparable to findings in other developed countries. Better outcomes were achieved in stage IV CCSK by using an intensive chemotherapy regimen including carboplatin, which require further confirmation by AREN0321. Lung RT may be safely omitted in selected patients who achieve a compete radiographic response after 6 weeks of systemic treatment (including surgery). Treatment should be encouraged even in CCSK cases with metastasis and relapse. [ABSTRACT FROM AUTHOR]

Neuroblastoma (NB) is the most commonly diagnosed extracranial solid tumor in children, accounting for 15% of all childhood cancer deaths. Although the 5-year survival rate of patients with a high-risk disease has increased in recent decades, NB remains a challenge in pediatric oncology, and the identification of novel potential therapeutic targets and agents is an urgent clinical need. The RNA-binding protein LIN28B has been identified as an oncogene in NB and is associated with a poor prognosis. Given that LIN28B acts by negatively regulating the biogenesis of the tumor suppressor let-7 miRNAs, we reasoned that selective interference with the LIN28B/let-7 miRNA interaction would increase let-7 miRNA levels, ultimately leading to reduced NB aggressiveness. Here, we selected (−)-epigallocatechin 3-gallate (EGCG) out of 4959 molecules screened as the molecule with the best inhibitory activity on LIN28B/let-7 miRNA interaction and showed that treatment with PLC/PLGA-PEG nanoparticles containing EGCG (EGCG-NPs) led to an increase in mature let-7 miRNAs and a consequent inhibition of NB cell growth. In addition, EGCG-NP pretreatment reduced the tumorigenic potential of NB cells in vivo. These experiments suggest that the LIN28B/let-7 miRNA axis is a good therapeutic target in NB and that EGCG, which can interfere with this interaction, deserves further preclinical evaluation. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Background: Neuroblastoma is one of the most common extracranial malignant solid tumors in children. AlkB homolog 5 (ALKBH5) is an RNA N6‐methyladenosine (m6A) demethylase that plays a critical role in tumorigenesis and development. We assessed the association between single nucleotide polymorphisms (SNPs) in ALKBH5 and the risk of neuroblastoma in a case‐control study including 402 patients and 473 non‐cancer controls. Methods: Genotyping was determined by the TaqMan method. The association between ALKBH5 polymorphisms (rs1378602 and rs8400) and the risk of neuroblastoma was evaluated using the odds ratio (OR) and 95% confidence interval (CI). Results: We found no strong association of ALKBH5 rs1378602 and rs8400 with neuroblastoma risk. Further stratification analysis by age, sex, primary site, and clinical stage showed that the rs1378602 AG/AA genotype was associated with a lower risk of neuroblastoma in males (adjusted OR = 0.58, 95% CI = 0.35–0.97, p = 0.036) and children with retroperitoneal neuroblastoma (adjusted OR = 0.58, 95% CI = 0.34–0.98, p = 0.040). Conclusions: ALKBH5 SNPs do not seem to be associated with neuroblastoma risk. More studies are required to confirm this negative result and reveal the relationship between gene polymorphisms of the m6A modifier ALKBH5 and neuroblastoma. [ABSTRACT FROM AUTHOR]

Simple Summary: The aim of this study was to analyze the safety and effectiveness of ICIs used in 42 pediatric patients with various types of highly advanced malignancies. Good outcomes were achieved in patients with malignant cutaneous melanoma or Hodgkin lymphoma. Age > 14 years and good performance status were favorable prognostic factors. Background/aim: The role of immune checkpoint inhibitors (ICIs; anti-PD1) in the treatment of childhood cancers is still evolving. The aim of this nationwide retrospective study was to assess the safety and effectiveness of ICIs used in a group of 42 patients, with a median age of 13.6 years, with various types of advanced malignancies treated in pediatric oncology centers in Poland between 2015 and 2023. Results: The indications for treatment with anti-PD1 were as follows: Hodgkin lymphoma (11); malignant skin melanoma (9); neuroblastoma (8); and other malignancies (14). At the end of follow-up, complete remission (CR) was observed in 37.7% (15/42) of children and disease stabilization in 9.5% (4/42), with a mean survival 3.6 (95% CI = 2.6–4.6) years. The best survival (OS = 1.0) was observed in the group of patients with Hodgkin lymphoma. For malignant melanoma of the skin, neuroblastoma, and other rare malignancies, the estimated 3-year OS values were, respectively, 0.78, 0.33, and 0.25 (p = 0.002). The best progression-free survival value (0.78) was observed in the group with malignant melanoma. Significantly better effects of immunotherapy were confirmed in patients ≥ 14 years of age and good overall performance ECOG status. Severe adverse events were observed in 30.9% (13/42) patients. [ABSTRACT FROM AUTHOR]

Wilms tumor (WT) represents over 90% of all pediatric kidney tumors. Children with WT often present acutely with hypertension which resolves in the short term after nephrectomy. However, WT survivors have increased long-term risk of hypertension, primarily due to decreased nephron mass after nephrectomy, with additional insults from possible exposure to abdominal radiation and nephrotoxic therapies. The diagnosis of hypertension may be improved by ambulatory blood pressure monitoring (ABPM), as several recent single-center studies have shown a substantial proportion of WT survivors with masked hypertension. Current gaps in knowledge include determining which WT patients may benefit from routine screening with ABPM, correlation of casual and ABPM parameters with cardiac abnormalities, and longitudinal assessment of cardiovascular and kidney parameters in relation to appropriate treatment of hypertension. This review aims to summarize the most recent literature on hypertension presentation and management at the time of WT diagnosis as well as the long-term hypertension risk and impact on kidney and cardiovascular outcomes in WT survivors. [ABSTRACT FROM AUTHOR]

Neuroblastoma is the most common extracranial solid tumor in children. The purpose of the present study is to detect the prognostic role and potential therapeutic efficacy of the T lymphoma invasion and metastasis 1 (Tiam1) in neuroblastoma. The overexpression of Tiam1 protein is frequently observed in neuroblastoma. Tiam1 expression is closely associated with adverse prognosis of neuroblastoma and risk group classification. Knockdown of TIAM1 by lentivirus expressing short hairpin RNA against TIAM1 (sh-TIAM1) inhibited the proliferation, invasion and cell-cycle progression, and promoted apoptosis of the neuroblastoma cell lines SH-SY5Y and SK-N-AS. Additionally, downregulation of the differentiation-related protein expression and decreased Rac1 expression was observed in the sh-TIAM1-transfected SH-SY5Y cells. In vivo, nude mice bearing TIAM1 knockdown SH-SY5Y cells showed improved overall survival and tumor growth suppression. The results demonstrate that inhibition of Tiam1 expression is a potential strategy for targeted therapy in neuroblastoma. [ABSTRACT FROM AUTHOR]

Introduction: Neuroblastoma (NB) is a common extracranial tumor in children and is highly heterogeneous. The factors influencing the prognosis of NB are not simple. Methods: To investigate the effect of cell senescence on the prognosis of NB and tumor immune microenvironment, 498 samples of NB patients and 307 cellular senescence-related genes were used to construct a prediction signature. Results: A signature based on six optimal candidate genes (TP53, IL-7, PDGFRA, S100B, DLL3, and TP63) was successfully constructed and proved to have good prognostic ability. Through verification, the signature had more advantages than the gene expression level alone in evaluating prognosis was found. Further T cell phenotype analysis displayed that exhausted phenotype PD-1 and senescencerelated phenotype CD244 were highly expressed in CD8+ T cell in MYCNamplified group with higher risk-score. Conclusion: A signature constructed the six MYCN-amplified differential genes and aging-related genes can be used to predict the prognosis of NB better than using each high-risk gene individually and to evaluate immunosuppressed and aging tumor microenvironment. [ABSTRACT FROM AUTHOR]

Simple Summary: Copy number abnormalities (CNAs) are frequent in neuroblastoma and used to determine treatments. Little is known about the role of structural variants (SVs) in disease progression. Optical genome mapping (OGM) uses label patterns to scan the genome which can be used to identify SVs in cancer. Currently, the detection of SVs still relies on standard cytogenetic techniques. We investigated the utility of OGM to detect SVs in neuroblastoma cell lines and tumours and compared it with standard cytogenetic techniques. OGM confirmed known CNAs and identified novel SVs of potential clinical significance. Background: Neuroblastoma is the most common extracranial solid tumour in children, accounting for 15% of paediatric cancer deaths. Multiple genetic abnormalities have been identified as prognostically significant in neuroblastoma patients. Optical genome mapping (OGM) is a novel cytogenetic technique used to detect structural variants, which has not previously been tested in neuroblastoma. We used OGM to identify copy number and structural variants (SVs) in neuroblastoma which may have been missed by standard cytogenetic techniques. Methods: Five neuroblastoma cell lines (SH-SY5Y, NBLW, GI-ME-N, NB1691 and SK-N-BE2(C)) and two neuroblastoma tumours were analysed using OGM with the Bionano Saphyr® instrument. The results were analysed using Bionano Access software and compared to previous genetic analyses including G-band karyotyping, FISH (fluorescent in situ hybridisation), single-nucleotide polymorphism (SNP) array and RNA fusion panels for cell lines, and SNP arrays and whole genome sequencing (WGS) for tumours. Results: OGM detected copy number abnormalities found using previous methods and provided estimates for absolute copy numbers of amplified genes. OGM identified novel SVs, including fusion genes in two cell lines of potential clinical significance. Conclusions: OGM can reliably detect clinically significant structural and copy number variations in a single test. OGM may prove to be more time- and cost-effective than current standard cytogenetic techniques for neuroblastoma. [ABSTRACT FROM AUTHOR]

Neuroblastoma is the most common extracranial solid tumor in children. Patients with neuroblastoma have a poor prognosis. The development of therapy targets and the ability to predict prognosis will be enhanced through further exploration of the genetically related genes of neuroblastoma. The present investigation utilized CRISPR-Cas9 genome-wide screening based on the DepMap database to determine essential genes for neuroblastoma cells' continued survival. WGCNA analysis was used to determine the progression-related genes, and a prognostic signature was constructed. The signature gene, NCAPG, was downregulated in neuroblastoma cells to explore its impact on various cellular processes. This research used DepMap and WGCNA to pinpoint 45 progression-related essential genes for neuroblastoma. A risk signature comprising NCAPG and MAD2L1 was established. The suppression of NCAPG prevented neuroblastoma cells from proliferating, migrating, and invading. The results of flow cytometric analysis demonstrated that NCAPG inhibition caused cell cycle arrest during the G2 and S phases and the activation of apoptosis. Additionally, NCAPG downregulation activated the p53-mediated apoptotic pathway, inducing cell apoptosis. The present work showed that NCAPG knockdown reduced neuroblastoma cell progression and may serve as a basis for further investigation into diagnostic indicators and therapy targets for neuroblastoma. [ABSTRACT FROM AUTHOR]

Neuroblastoma is the most common extracranial solid tumor in children. A subgroup of high-risk patients is characterized by aberrations in the chromatin remodeller ATRX that is encoded by 35 exons. In contrast to other pediatric cancer where ATRX point mutations are most frequent, multi-exon deletions (MEDs) are the most frequent type of ATRX aberrations in neuroblastoma. 75% of these MEDs are predicted to produce in-frame fusion proteins, suggesting a potential gain-of-function effect compared to nonsense mutations. For neuroblastoma there are only a few patient-derived ATRX aberrant models. Therefore, we created isogenic ATRX aberrant models using CRISPR-Cas9 in several neuroblastoma cell lines and one tumoroid and performed total RNA-sequencing on these and the patient-derived models. Gene set enrichment analysis (GSEA) showed decreased expression of genes related to both ribosome biogenesis and several metabolic processes in our isogenic ATRX exon 2–10 MED model systems, the patient-derived MED models and in tumor data containing two patients with an ATRX exon 2–10 MED. In sharp contrast, these same processes showed an increased expression in our isogenic ATRX knock-out and exon 2–13 MED models. Our validations confirmed a role of ATRX in the regulation of ribosome homeostasis. The two distinct molecular expression patterns within ATRX aberrant neuroblastomas that we identified imply that there might be a need for distinct treatment regimens. [ABSTRACT FROM AUTHOR]

Retinoblastoma (RB) is a childhood cancer that forms in the developing retina of young children; this tumor cannot be biopsied due to the risk of provoking extraocular tumor spread, which dramatically alters the treatment and survival of the patient. Recently, aqueous humor (AH), the clear fluid in the anterior chamber of the eye, has been developed as an organ-specific liquid biopsy for investigation of in vivo tumor-derived information found in the cell-free DNA (cfDNA) of the biofluid. However, identifying somatic genomic alterations, including both somatic copy number alterations (SCNAs) and single nucleotide variations (SNVs) of the RB1 gene, typically requires either: (1) two distinct experimental protocols—low-pass whole genome sequencing for SCNAs and targeted sequencing for SNVs—or (2) expensive deep whole genome or exome sequencing. To save time and cost, we applied a one-step targeted sequencing method to identify both SCNAs and RB1 SNVs in children with RB. High concordance (median = 96.2%) was observed in comparing SCNA calls derived from targeted sequencing to the traditional low-pass whole genome sequencing method. We further applied this method to investigate the degree of concordance of genomic alterations between paired tumor and AH samples from 11 RB eyes. We found 11/11 AH samples (100%) had SCNAs, and 10 of them (90.1%) with recurrent RB-SCNAs, while only nine out of 11 tumor samples (81.8%) had positive RB-SCNA signatures in both low-pass and targeted methods. Eight out of the nine (88.9%) detected SNVs were shared between AH and tumor samples. Ultimately, 11/11 cases have somatic alterations identified, including nine RB1 SNVs and 10 recurrent RB-SCNAs with four focal RB1 deletions and one MYCN gain. The results presented show the feasibility of utilizing one sequencing approach to obtain SCNA and targeted SNV data to capture a broad genomic scope of RB disease, which may ultimately expedite clinical intervention and be less expensive than other methods. [ABSTRACT FROM AUTHOR]

Simple Summary: Specific recurrent segmental aberrations (SCA) have been associated with poor survival in neuroblastoma (NB). The effect of many other not recurrent SCA has not been clarified yet. Here we examined the role of the loss of chromosome 10q in a cohort of 260 NB primary tumors, observing a lower survival rate for the patients expressing this rare SCA. We identified a cluster of 75 genes in the long arm of chromosome 10, whose deletion was associated with poorer survival. Six genes, and in particular CCSER2, appeared to be good candidates to play a role as tumor suppressor genes in NB and possible targets for future therapeutic interventions. Neuroblastoma (NB) is a tumor affecting the peripheral sympathetic nervous system that substantially contributes to childhood cancer mortality. Despite recent advances in understanding the complexity of NB, the mechanisms determining its progression are still largely unknown. Some recurrent segmental chromosome aberrations (SCA) have been associated with poor survival. However, the prognostic role of most SCA has not yet been investigated. We examined a cohort of 260 NB primary tumors at disease onset for the loss of chromosome 10q, by array-comparative genomic hybridization (a-CGH) and Single Nucleotide Polymorphism (SNP) array and we found that 26 showed 10q loss, while the others 234 displayed different SCA. We observed a lower event-free survival for NB patients displaying 10q loss compared to patients with tumors carrying other SCA. Furthermore, analyzing the region of 10q loss, we identified a cluster of 75 deleted genes associated with poorer outcome. Low expression of six of these genes, above all CCSER2, was significantly correlated to worse survival using in silico data from 786 NB patients. These potential tumor suppressor genes can be partly responsible for the poor prognosis of NB patients with 10q loss. [ABSTRACT FROM AUTHOR]

Simple Summary: Until recently, the prevalence of hereditary cancer in children was estimated to be very low. However, recent studies suggest that at least 10% of pediatric cancer patients have a germline mutation in a cancer predisposition gene. It has been shown that most of these mutations affect splicing, a process by which different transcripts of the same gene are produced. The splicing process is very important, as it regulates many aspects of cellular proliferation, survival, and differentiation. Hereditary cancer genes are highly prone to splicing alterations, and among them there are several genes that may contribute to the development of pediatric solid tumors when mutated in the germline. In this review, we analyze the importance of the splicing-disrupting mutations in pediatric solid cancer and inherited predisposition syndromes. The therapies developed to correct aberrant splicing in cancer are also discussed. The prevalence of hereditary cancer in children was estimated to be very low until recent studies suggested that at least 10% of pediatric cancer patients carry a germline mutation in a cancer predisposition gene. A significant proportion of pathogenic variants associated with an increased risk of hereditary cancer are variants affecting splicing. RNA splicing is an essential process involved in different cellular processes such as proliferation, survival, and differentiation, and alterations in this pathway have been implicated in many human cancers. Hereditary cancer genes are highly susceptible to splicing mutations, and among them there are several genes that may contribute to pediatric solid tumors when mutated in the germline. In this review, we have focused on the analysis of germline splicing-disrupting mutations found in pediatric solid tumors, as the discovery of pathogenic splice variants in pediatric cancer is a growing field for the development of personalized therapies. Therapies developed to correct aberrant splicing in cancer are also discussed as well as the options to improve the diagnostic yield based on the increase in the knowledge in splicing. [ABSTRACT FROM AUTHOR]

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

Purpose: Neuroblastoma (NB) is the most frequent extracranial tumor in children. The detection of bone marrow (BM) involvement is crucial for correct staging and risk-adapted treatment. We compared three methods regarding the detection of NB involvement in BM. Methods: Eighty-one patients with NB were included in this retrospective study. BM samples were obtained at designated time points at study entry and during treatment or follow-up. The diagnostic tools for BM analysis included cytomorphology (CM), flow cytometry (FCM) and automatic immunofluorescence plus fluorescence in situ hybridization (AIPF). Results: We analyzed 369 aspirates in 81 patients in whom AIPF, CM, and FCM were simultaneously available. During the observation period, NB cells were detected in 86/369 (23.3%) cases, by CM in 32/369 (8.7%), by FCM in 52 (14.1%), and by AIPF in 72 (19.5%) samples. AIPF and/or FCM confirmed all positive results obtained in CM and detected 11 additional positive BM aspirates in 294 CM negative samples (p < 0,001). Survival of patients with BM involvement at study entry identified solely by FCM/AIPF was 17.4% versus 0% for patients in whom BM involvement was already identified by CM. Conclusion: The combination of AIPF/FCM yielded the highest detection rate of NB cells in BM. AIPF was the single, most sensitive method in detecting these cells. Although CM did not provide any additional positive results, it is still a useful, readily available and cost-effective tool. The prognostic significance of FCM and AIPF should be confirmed in a prospective study with a larger number of patients. [ABSTRACT FROM AUTHOR]

Neuroblastoma (NB) is a pediatric neuroendocrine neoplasm. It arises from the sympatho-adrenal lineage of neural-crest-derived multipotent progenitor cells that fail to differentiate. NB is the most common extracranial tumor in children, and it manifests undisputed heterogeneity. Unsatisfactory outcomes of high-risk (HR) NB patients call for more research to further inter-relate treatment and molecular features of the disease. In this regard, it is well established that in the tumor microenvironment (TME), malignant cells are engaged in complex and dynamic interactions with the extracellular matrix (ECM) and stromal cells. The ECM can be a source of both pro- and anti-tumorigenic factors to regulate tumor cell fate, such as survival, proliferation, and resistance to therapy. Moreover, the ECM composition, organization, and resulting signaling networks are vastly remodeled during tumor progression and metastasis. This review mainly focuses on the molecular mechanisms and effects of interactions of selected ECM components with their receptors on neuroblastoma cells. Additionally, it describes roles of enzymes modifying and degrading ECM in NB. Finally, the article gives examples on how the knowledge is exploited for prognosis and to yield new treatment options for NB patients. [ABSTRACT FROM AUTHOR]

Simple Summary: Metabolic reprogramming has a central role in the initiation and progression of cancer, including high-risk neuroblastoma, a deadly childhood malignant tumor of the sympathetic nervous system. This rewiring of cellular metabolism increases the manufacture of fuel and building blocks for biomass production, which is essential to sustain the growth and proliferation of neuroblastoma cells. However, the rewiring also makes neuroblastoma cells metabolically distinct from normal sympathetic neurons, thereby offering new therapeutic opportunities. In this review, we summarize the recent progress in the study of neuroblastoma metabolic reprogramming and underlying molecular mechanisms. Neuroblastoma is a pediatric cancer responsible for approximately 15% of all childhood cancer deaths. Aberrant MYCN activation, as a result of genomic MYCN amplification, is a major driver of high-risk neuroblastoma, which has an overall survival rate of less than 50%, despite the best treatments currently available. Metabolic reprogramming is an integral part of the growth-promoting program driven by MYCN, which fuels cell growth and proliferation by increasing the uptake and catabolism of nutrients, biosynthesis of macromolecules, and production of energy. This reprogramming process also generates metabolic vulnerabilities that can be exploited for therapy. In this review, we present our current understanding of metabolic reprogramming in neuroblastoma, focusing on transcriptional regulation as a key mechanism in driving the reprogramming process. We also highlight some important areas that need to be explored for the successful development of metabolism-based therapy against high-risk neuroblastoma. [ABSTRACT FROM AUTHOR]

Adolescent cancer patients and their caregivers have demonstrated willingness to participate in invasive biological sampling, either for their own potential benefit or for research purposes. However, many malignancies occur primarily in prepubescent patients and there are no similar studies in this population. Our study objective was to assess the willingness of caregivers to consent to research studies involving invasive biological sampling in children ≤ 13 years of age. Participants completed a survey assessing their willingness to allow various procedures both with and without clinical benefit to their children. Most respondents were willing to allow additional blood draws regardless of potential benefit to their children (95.6% were willing when there would be benefits and 95.6% were willing when there would not). Although the overall willingness was lower with other hypothetical procedures, the majority of respondents were still willing to allow additional biopsies for research purposes. Caregivers of young children with cancer will allow their children to undergo additional invasive procedures for research purposes. This willingness decreased with more invasive procedures without potential direct benefit, but interest remained in more than half of participants. Caregivers for young patients with cancer should be approached for participation in future biological/correlative studies. [ABSTRACT FROM AUTHOR]

Simple Summary: Precision oncology requires tumor molecular profiling to identify actionable targets. Blood-derived liquid biopsy (LB) is a potential alternative that is not yet documented in real-world settings, especially in pediatric oncology. Analyzing, retrospectively, the use of LB in children with refractory relapsing diseases, we were able to show that this is a feasible alternative to tissue biopsy, resulting in successful analysis in a subset of patients. Precision oncology requires tumor molecular profiling to identify actionable targets. Tumor biopsies are considered as the gold standard, but their indications are limited by the burden of procedures in children. Blood-derived liquid biopsy (LB) is a potential alternative that is not yet documented in real-world settings, especially in pediatric oncology. We performed a retrospective analysis of children and teenagers with a relapsing or refractory disease, upon whom LB was performed using the Foundation One® liquid CDx from 1 January 2020 to 31 December 2021 in a single center. Forty-five patients (27 boys) were included, with a median age of 9 years of age (range: 1.5–17 years old). Underlying malignancies were neuroblastoma (12 patients), bone sarcoma (12), soft tissue sarcoma (9), brain tumors (7), and miscellaneous tumors (5). Forty-three patients had metastatic disease. Six patients had more than one biopsy because of a failure in first LB. Median time to obtain results was 13 days. Overall, analysis was successful for 33/45 patients. Eight patients did not present any molecular abnormalities. Molecular alterations were identified in 25 samples with a mean of 2.1 alterations per sample. The most common alterations concerned TP53 (7 pts), EWS-FLI1 (5), ALK (3), MYC (3), and CREBBP (2). TMB was low in all cases. Six patients received treatment based on the results from LB analysis and all were treated off-trial. Three additional patients were included in early phase clinical trials. Mean duration of treatment was 85 days, with one patient with stable disease after eight months. Molecular profiling using Foundation One® Liquid CDx was feasible in pediatric patients with high-risk solid tumors and lead to identification of targetable mutations in a subset of patients. [ABSTRACT FROM AUTHOR]

Objective: Neuroblastoma (NB) is the most common extracranial solid tumor in children and is responsible for 12% of cancer-related deaths. The status of metastatic disease in the bone marrow (BM) is a predictor of poor outcome. The purpose of this study was to investigate the predictive significance of histopathological examination of BM in NB. Material and Method: The study included 61 cases with archival bone marrow biopsy tissues. The cases were evaluated regarding the percentage of metastatic tissue and its differentiation. Primary tumor slides were also reviewed to perform the Shimada classification based on the differentiation status and mitosis-karyorrhexis index. The patients' age, gender, NMYC amplification, clinical risk group, and disease outcome were also noted. Results: Of the 61 cases, 17 had BM involvement. Of those, eight cases (47.1%) were refractory NB showing disease relapse. Based on BM examination, five cases (29.4%) were categorized as complete response, seven (41.2%) as progressive disease, three (17.6%) as minimal disease, and two (11.8%) as stable disease. The progressive disease category was significantly related with refractory disease and NMYC amplification along with the high-risk category (p =0.002 and p= 0.003 respectively). Undifferentiated histology and presence of more than 20% of tumor tissue in the BM biopsy at diagnosis were significantly associated with the progressive disease category (p=0.01 and p<0.001, respectively). Conclusion: We conclude that evaluating the percentage of metastatic tumor tissue and tumor differentiation in BM biopsies is of clinical importance in the management of neuroblastoma patients. [ABSTRACT FROM AUTHOR]

Background: Pyroptosis, as an inflammatory form of cell death, is involved in many physiological and pathological processes. Neuroblastoma is the most common extra-cranial solid tumor in children. In this study, the relationship between pyroptosis and tumor microenvironment in neuroblastoma was systematically studied. Methods: We integrated four datasets of neuroblastomas. Through robust clustering of the mRNA expression profiles of 24 pyroptosis-related genes, a total of three pyroptosis patterns were identified. We then constructed a novel scoring method named as pyroscore to quantify the level of pyroptosis in neuroblastoma. Multi-omics data and single-cell RNA sequencing were used to accurately and comprehensively evaluate the effectiveness of pyroscore. Clinical data sets were used to evaluate the use of pyroscore to predict the responsiveness of immune checkpoint treatment. Results: High pyroscore was associated with good prognosis, immune activation, and increased response to checkpoint blockade immunotherapy. Multivariate Cox analysis revealed that the pyroscore was an independent prognostic biomarker and could increase the accuracy of clinical prediction models. Etoposide, a drug picked up by our analysis, could increase the sensitivity of neuroblastoma cells to pyroptosis. External verification using four cohorts of patients who had received immunotherapy showed that high pyroscore was significantly associated with immunotherapy treatment benefit. Conclusions: Taken together, this study revealed that pyroptosis-related gene network could quantify the response of neuroblastoma to immune checkpoint blockade therapy and prognosis, and it may be helpful for clinical practitioners to choose treatment strategies for neuroblastoma patients. [ABSTRACT FROM AUTHOR]

Around 6% of all childhood malignancies represent renal tumors, of which a majority includes Wilms tumor (WT). Although survival rates have improved over the last decades, specific patients are still at risk for adverse outcome. In the Netherlands, since 2015, pediatric oncology care for renal tumors has been centralized in the Princess Máxima Center for Pediatric Oncology. Here, we describe experiences of the first 5 years of centralized care and explore whether this influences the epidemiological landscape by comparing data with the Netherlands Cancer Registry (NCR). We identified all patients <19 years with a renal mass diagnosed between 01-01-2015 and 31-12-2019 in the Princess Máxima Center. Epidemiology, characteristics and management were analyzed. We identified 164 patients (including 1 patient who refused consent for registration), in our center with a suspicion of a renal tumor. The remaining 163 cases included WT (n = 118)/cystic partially differentiated nephroblastoma (n = 2)/nephrogenic rests only (n = 6) and non-WT (n = 37). In this period, the NCR included 138 children, 1 17-year-old patient was not referred to the Princess Máxima Center. Central radiology review (before starting treatment) was performed in 121/163 patients, and central pathology review in 148/152 patients that underwent surgery. Treatment stratification, according to SIOP/EpSSG protocols was pursued based on multidisciplinary consensus. Preoperative chemotherapy was administered in 133 patients, whereas 19 patients underwent upfront surgery. Surgery was performed in 152 patients, and from 133 biomaterial was stored. Centralization of care for children with renal tumors led to referral of all but 1 new renal tumor cases in the Netherlands, and leads to referral of very rare subtypes not registered in the NCR, that benefit from high quality diagnostics and multidisciplinary decision making. National centralization of care led to enhanced development of molecular diagnostics and other innovation-based treatments for the future. [ABSTRACT FROM AUTHOR]

Background: Thoracic inlet (TI) tumors are rare, and can be particularly challenging to resect due to proximity to mediastinal vessels and nerves. Traditional resection is typically performed through "trapdoor" or sternoclavicular incisions. The purpose of our study was to evaluate the feasibility and effectiveness of thoracoscopic resection of this group of tumors. Methods: We performed a single-center retrospective chart review for children who presented with TI neuroblastic tumors between 2011 and 2020. Demographics, tumor characteristics, treatment, operative complications, and outcomes were collected and analyzed. Results: Eight patients were identified. The median age at diagnosis was 13 months (interquartile range [IQR] 6-32) with median tumor size at diagnosis of 4.1 cm (IQR 3.6-4.4). Neoadjuvant chemotherapy was given in 50% (4/8) with 38% (3/8) undergoing upfront surgery; 1 patient was observed without chemotherapy or surgery. Ultimately, 6 patients had thoracoscopic resection. For thoracoscopic resections, median intraoperative estimated blood loss was 15 mL (IQR 10-28), median operative room time was 199 minutes (IQR 152-259), and median hospital length of stay was 2 days (IQR 2-3). There were two complications: one recurrent laryngeal nerve injury and one new-onset Horner's syndrome. Complete gross total resection was achieved for all children and there were no recurrences or mortalities with a median follow-up of 3 years. Conclusion: Thoracoscopic resection for TI neuroblastic tumors is feasible with minimal morbidity and can lead to adequate oncological resection. [ABSTRACT FROM AUTHOR]

Background: Neuroblastoma (NB) is the most common extracranial solid tumor in children. Interference with the polyamine biosynthesis pathway by inhibition of MYCN-activated ornithine decarboxylase (ODC) is a validated approach. The ODC inhibitor α-difluoromethylornithine (DFMO, or Eflornithine) has been FDA-approved for the treatment of trypanosomiasis and hirsutism and has advanced to clinical cancer trials including NB as well as cancer-unrelated human diseases. One key challenge of DFMO is its rapid renal clearance and the need for high and frequent drug dosing during treatment. Methods: We performed in vivo pharmacokinetic (PK), antitumorigenic, and molecular studies with DFMO/probenecid using NB patient-derived xenografts (PDX) in mice. We used LC–MS/MS, HPLC, and immunoblotting to analyze blood, brain tissue, and PDX tumor tissue samples collected from mice. Results: The organic anion transport 1/3 (OAT 1/3) inhibitor probenecid reduces the renal clearance of DFMO and significantly increases the antitumor activity of DFMO in PDX of NB (P < 0.02). Excised tumors revealed that DFMO/probenecid treatment decreases polyamines putrescine and spermidine, reduces MYCN protein levels and dephosphorylates retinoblastoma (Rb) protein (p-RbSer795), suggesting DFMO/probenecid-induced cell cycle arrest. Conclusion: Addition of probenecid as an adjuvant to DFMO therapy may be suitable to decrease overall dose and improve drug efficacy in vivo. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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Progresses over the past years have extensively improved our capacity to use genome-scale analyses—including high-density genotyping and exome and genome sequencing—to identify the genetic basis of pediatric tumors. In particular, exome sequencing has contributed to the evidence that about 10% of children and adolescents with tumors have germline genetic variants associated with cancer predisposition. In this review, we provide an overview of genetic variations predisposing to solid pediatric tumors (medulloblastoma, ependymoma, astrocytoma, neuroblastoma, retinoblastoma, Wilms tumor, osteosarcoma, rhabdomyosarcoma, and Ewing sarcoma) and outline the biological processes affected by the involved mutated genes. A careful description of the genetic basis underlying a large number of syndromes associated with an increased risk of pediatric cancer is also reported. We place particular emphasis on the emerging view that interactions between germline and somatic alterations are a key determinant of cancer development. We propose future research directions, which focus on the biological function of pediatric risk alleles and on the potential links between the germline genome and somatic changes. Finally, the importance of developing new molecular diagnostic tests including all the identified risk germline mutations and of considering the genetic predisposition in screening tests and novel therapies is emphasized. [ABSTRACT FROM AUTHOR]

Purpose: Wilms tumor (WT), or nephroblastoma, is an embryonic tumor that constitutes the most common renal tumor in children. Little is known about the etiology of WT. The aim of this study was to investigate whether maternal or perinatal characteristics were associated with the risk of WT.Methods: The ESTELLE study is a national-based case-control study that included 117 cases of WT and 1,100 controls younger than 11 years old. The cases were children diagnosed in France in 2010-2011 and the controls were frequency matched with cases by age and gender. The mothers of case and control children responded to a telephone questionnaire addressing sociodemographic and perinatal characteristics, childhood environment, and lifestyle. Unconditional logistic regression models adjusted on potential cofounders were used to estimate the odds ratios (OR) and their confidence intervals (95% CI).Results: High birth weight and the presence of congenital malformation were associated with WT (OR 1.9 [95% CI 1.0-3.7] and OR 2.5 [95% CI 1.1-5.8], respectively). No association with breastfeeding or folic acid supplementation was observed.Conclusions: Although potential recall bias cannot be excluded, our findings reinforce the hypothesis that high birth weight and the presence of congenital malformation may be associated with an increased risk of WT. Further investigations are needed to further elucidate the possible role of maternal characteristics in the etiology of WT. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the impact of local therapies on high-risk neuroblastoma (HR-NB) outcomes in South Africa.Methods: Data from 295 patients with HR-NB from nine pediatric oncology units between 2000 and 2014 were analysed. All patients received chemotherapy. Five-year overall (OS) and event free survival (EFS) were determined for patients who had received local therapy, either surgery or radiotherapy or both.Results: Surgery was performed in only 35.9% (n = 106/295) patients. Surgical excision was done for 34.8% (n = 85/244) of abdominal primaries, 50.0% (n = 11/22) of thoracic primaries; 22.2% (n = 2/9) neck primaries and 66.7% (n = 8/12) of the paraspinal primaries. Only 15.9% (n = 47/295) of all patients received radiotherapy. Children, who had surgery, had an improved five-year OS of 32.1% versus 5.9% without surgery (p < 0.001). Completely resected disease had a five-year OS of 30.5%, incomplete resections 31.4% versus no surgery 6.0% (p < 0.001). Radiated patients had a five-year OS of 21.3% versus 14.2% without radiotherapy (p < 0.001). Patients who received radiotherapy without surgical interventions, had a marginally better five-year OS of 12.5% as opposed to 5.4% (p < 0.001). Patients who underwent surgery had a longer mean overall survival of 60.9 months, while patients, who were irradiated, had a longer mean overall survival of 7.9 months (p < 0.001). On multivariate analysis, complete metastatic remission (p < 0.001), surgical status (p = 0.027), and radiotherapy status (p = 0.040) were significant predictive factors in abdominal primaries.Conclusion: Surgery and radiotherapy significantly improve outcomes regardless of the primary tumor site, emphasizing the importance of local control in neuroblastoma. [ABSTRACT FROM AUTHOR]

Cell-free DNA profiling using patient blood is emerging as a non-invasive complementary technique for cancer genomic characterization. Since these liquid biopsies will soon be integrated into clinical trial protocols for pediatric cancer treatment, clinicians should be informed about potential applications and advantages but also weaknesses and potential pitfalls. Small retrospective studies comparing genetic alterations detected in liquid biopsies with tumor biopsies for pediatric solid tumor types are encouraging. Molecular detection of tumor markers in cell-free DNA could be used for earlier therapy response monitoring and residual disease detection as well as enabling detection of pathognomonic and therapeutically relevant genomic alterations.Conclusion: Existing analyses of liquid biopsies from children with solid tumors increasingly suggest a potential relevance for molecular diagnostics, prognostic assessment, and therapeutic decision-making. Gaps remain in the types of tumors studied and value of detection methods applied. Here we review the current stand of liquid biopsy studies for pediatric solid tumors with a dedicated focus on cell-free DNA analysis. There is legitimate hope that integrating fully validated liquid biopsy-based innovations into the standard of care will advance patient monitoring and personalized treatment of children battling solid cancers.What is Known:• Liquid biopsies are finding their way into routine oncological screening, diagnosis, and disease monitoring in adult cancer types fast.• The most widely adopted source for liquid biopsies is blood although other easily accessible body fluids, such as saliva, pleural effusions, urine, or cerebrospinal fluid (CSF) can also serve as sources for liquid biopsiesWhat is New:• Retrospective proof-of-concept studies in small cohorts illustrate that liquid biopsies in pediatric solid tumors yield tremendous potential to be used in diagnostics, for therapy response monitoring and in residual disease detection.• Liquid biopsy diagnostics could tackle some long-standing issues in the pediatric oncology field; they can enable accurate genetic diagnostics in previously unbiopsied tumor types like renal tumors or brain stem tumors leading to better treatment strategies. [ABSTRACT FROM AUTHOR]

Background: Neuroblastoma (NB) is the most common extracranial solid tumor found in children. The frequent gain/loss of many chromosome bands in tumor cells and absence of mutations found at diagnosis suggests that NB is a copy number-driven cancer. Despite the previous work, a systematic analysis that investigates the relationship between such frequent gain/loss of chromosome bands and patient prognosis has yet to be implemented. Methods: First, we analyzed two NB CNV datasets to select chromosomal bands with a high frequency of gain or loss. Second, we applied a computational approach to infer sample-specific CNVs for each chromosomal band selected in step 1 based on gene expression data. Third, we applied univariate Cox proportional hazards models to examine the association between the resulting inferred copy number values (iCNVs) and patient survival. Finally, we applied multivariate Cox proportional hazards models to select chromosomal bands that remained significantly associated with prognosis after adjusting for critical clinical variables, including age, stage, gender, and MYCN amplification status. Results: Here, we used a computational method to infer the copy number variations (CNVs) of sample-specific chromosome bands from NB patient gene expression profiles. The resulting inferred CNVs (iCNVs) were highly correlated with the experimentally determined CNVs, demonstrating CNVs can be accurately inferred from gene expression profiles. Using this iCNV metric, we identified 58 frequent gain/loss chromosome bands that were significantly associated with patient survival. Furthermore, we found that 7 chromosome bands were still significantly associated with patient survival even when clinical factors, such as MYCN status, were considered. Particularly, we found that the chromosome band chr11p14 has high potential as a novel candidate cytogenetic biomarker for clinical use. Conclusion: Our analysis resulted in a comprehensive list of prognostic chromosome bands supported by strong statistical evidence. In particular, the chr11p14 gain event provided additional prognostic value in addition to well-established clinical factors, including MYCN status, and thereby represents a novel candidate cytogenetic biomarker with high clinical potential. Additionally, this computational framework could be readily extended to other cancer types, such as leukemia. [ABSTRACT FROM AUTHOR]

Background: Despite the lack of randomized or controlled trials for minimally invasive surgery (MIS) in pediatric surgical oncology, the integration of MIS into the surgical practice of pediatric oncology has become increasingly popular. The aim of this study was to evaluate the implementation of MIS in a pediatric tertiary cancer center and compare present use of MIS to that in a previous analysis at our center. Methods: We retrospectively reviewed the medical records of patients with pediatric cancer treated with MIS at a single institution between 2000 and 2014. Results: A total of 252 MIS procedures were performed: 73 laparoscopic (29%) and 179 thoracoscopic (71%). MIS was used for diagnostic purposes in 59% (146 thoracoscopic and 34 laparoscopic) and the therapeutic resection in 24% (39 laparoscopic cases and 33 thoracoscopic cases). Conversion to an open procedure occurred in 18 tumor resections (6%) and in 22 diagnostic biopsies (7%), mostly due to technical challenges in identifying or mobilizing tumors. Complications occurred in seven tumor resections (2%) and included three pneumothoraces, two bleeding complications, one bowel injury, and one wound infection. Complications occurred in 10 diagnostic biopsies (3%), mostly pneumothoraces. No tumor upstaging or trocar site recurrences occurred (follow-up time, 1-15 years). Conclusions: Over the last decade, we demonstrate the evolution of MIS in the management of solid tumors in children. We encourage surgeons and oncologists to join the call to arms to establish prospective trials evaluating MIS in pediatric surgical oncology. [ABSTRACT FROM AUTHOR]

Neuroblastoma, a malignant neoplasm of the sympathetic nervous system, is one of the most aggressive pediatric cancers. Patients with stage IV high-risk neuroblastoma receive an intensive multimodal therapy ending with an immunotherapy based on a chimeric monoclonal antibody ch14.18. Although the use of ch14.18 monoclonal antibody has significantly increased the survival rate of high-risk neuroblastoma patients, about 33% of these patients still relapse and die from their disease. Ch14.18 targets the disialoganglioside, GD2, expressed on neuroblastic tumor (NT) cells. To better understand the causes of tumor relapse following ch14.18 immunotherapy, we have analyzed the expression of GD2 in 152 tumor samples from patients with NTs using immunohistochemical stainings. We observed GD2 expression in 146 of 152 samples (96%); however, the proportion of GD2-positive cells varied among samples. Interestingly, low percentage of GD2-positive cells before immunotherapy was associated with relapse in patients receiving ch14.18 immunotherapy. In addition, we demonstrated in vitro that the sensitivity of neuroblastoma cell lines to natural killer-mediated lysis was dependent on the proportion of GD2-positive cells, in the presence of ch14.18 antibody. In conclusion, our results indicate that the proportion of tumor cells expressing GD2 in NTs should be taken in consideration, as a prognostic marker, for high-risk neuroblastoma patients receiving anti-GD2 immunotherapy. [ABSTRACT FROM AUTHOR]

Background: Chemotherapy is one of major therapeutic regimens for neuroblastoma (NB) in children. However, recurrence and metastasis associated with poor prognosis caused by acquired multidrug resistance remains a challenge. There is a great need to achieve new insight into the molecular mechanism of drug resistance in NB. The aim of this study is to identify novel drug sensitivity-related biomarkers as well as new therapeutic targets to overcome chemoresistance. Methods: We proteome-wide quantitatively compared protein expression of two NB cell lines with different drug sensitivities, isolated from the same patient prior to and following chemotherapy. Annexin A2 (ANXA2) emerged as a key factor contributing to drug resistance in NB. Then, we assessed the correlation of ANXA2 expression and clinical characteristics using a tissue microarray. Further, the roles of ANXA2 in chemoresistance for NB and the underlying mechanisms were studied by using short hairpin RNA (shRNA) in vitro and vivo. Results: First in total, over 6000 proteins were identified, and there were about 460 significantly regulated proteins which were up- or down-regulated by greater than two folds. We screened out ANXA2 which was upregulated by more than 12-fold in the chemoresistant NB cell line, and it might be involved in the drug resistance of NB. Then, using a tissue chip containing 42 clinical NB samples, we found that strong expression of ANXA2 was closely associated with advanced stage, greater number of chemotherapy cycles, tumor metastasis and poor prognosis. Following knockdown of ANXA2 in NB cell line SK-N-BE(2) using shRNA, we demonstrate enhanced drug sensitivity for doxorubicin (2.77-fold) and etoposide (7.87-fold) compared with control. Pro-apoptotic genes such as AIF and cleaved-PARP were upregulated. Inhibiting ANXA2 expression attenuated transcriptional activity of NF-κB via down-regulated nuclear translocation of subunit p50. Finally, simulated chemotherapy in a xenograft NB nude mouse model suggests that ANXA2 knockdown could improve clinical results in vivo. Conclusion: Our profiling data provided a rich source for further study of the molecular mechanisms of acquired drug resistance in NB. Further study may determine the role of ANXA2 as a prognostic biomarker and a potential therapeutic target for patients with multidrug-resistant NB. [ABSTRACT FROM AUTHOR]

Background: Childhood neuroblastoma describes a heterogeneous group of extracranial solid tumors, that are treated per risk profile. We sought to describe treatment patterns and survival using population-based data from throughout the United States. Materials and Methods: Using the National Cancer Institute (NCI)'s Patterns of Care data, we analyzed treatment provided to newly diagnosed, histologically confirmed neuroblastoma patients in 2010 and 2011, registered to one of 14 Surveillance, Epidemiology, and End Results (SEER) cancer registries. Data were re-abstracted from hospital records and treating physicians contacted for verification. Application of the Children's Oncology Group (COG)'s 3-level (low, intermediate and high) neuroblastoma risk classification system for therapeutic decision-making provided insight to community-based treatment patterns. Kaplan-Meier survival analyses, based on 5-years of follow-up, were also performed. Results: 76% of the 250 patients were enrolled on an open/active clinical trial. All low-risk patients received surgery. Most intermediate-risk patients (81%) received a chemotherapy regimen that included carboplatin, etoposide, cyclophosphamide and doxorubicin. High-risk patients received extensive, multimodal treatment consisting of chemotherapy, surgery, myeloablative chemotherapy with stem cell rescue (transplant), radiation, immunotherapy (dinutuximab), and isotretinoin therapy. 21% patients had died at the end of the maximum 60-month follow-up period. The 5-year estimated survival rates were lower for patients diagnosed with stage 4 disease, unfavorable DNA ploidy, MYCN gene amplification or classified as high-risk. Conclusion: Most neuroblastoma patients are registered on a risk-based open/active clinical trial. Variation in modality, systemic agents and sequence of treatment reflects the heterogeneity of therapy received by these patients. [ABSTRACT FROM AUTHOR]

The authors offer observation on the Children's Oncology Group (COG) trial ANBL0532, which examined the effect of tandem autologous stem cell transplant versus single transplant on event-free survival (EFS) in patients with high-risk neuroblastoma. Topics discussed include reason neuroblastoma remains challenging despite improvement in survival rates, strengths of the study, and current-era therapy for patients with high-risk neuroblastoma.

Background: The aetiology of neuroblastic tumours is unclear with both genetic and environmental factors implicated. The possibility that an infectious agent may be involved has been suggested. 'Temporal clustering' occurs if cases display an irregular temporal distribution and may indicate the involvement of an agent that exhibits epidemicity. We tested for the presence and nature of temporal clustering using population-based data from northern England. Methods: We extracted all cases of neuroblastic tumours diagnosed in children and young adults aged 0-24 years during 1968-2011 from the Northern Region Young Persons' Malignant Disease Registry. This is a population-based registry, covering a population of approximately 900,000 young persons, and includes all cases resident in northern England at the time of diagnosis. Tests for temporal clustering were applied using a modified version of the Potthoff-Whittinghill method. Estimates of extra-Poisson variation (β̂) and standard errors (SEs) were obtained. Results: 227 cases of neuroblastic tumours were diagnosed during the study period. All the analyses between fortnights and between months found significant extra-Poisson variation, with β̂ =0.846 (SE = 0.310, P = 0.004) for the analysis between fortnights within months. Restricting the analyses to the 76 cases diagnosed at ages less than 18 months showed significant extra-Poisson variation between fortnights within months (β̂ =1.532, SE = 0.866, P = 0.038), but not between months. In contrast, analyses of cases aged 18 months to 24 years showed significant extra-Poisson variation between quarters within years, as well as over shorter timescales. Conclusions: Transient environmental agents may be involved in the aetiology of neuroblastic tumours. The initiating factor might be a geographically-widespread agent that occurs in 'mini-epidemics'. [ABSTRACT FROM AUTHOR]

Background:The prognostic impact of segmental chromosome alterations (SCAs) in children older than 1 year, diagnosed with localised unresectable neuroblastoma (NB) without MYCN amplification enrolled in the European Unresectable Neuroblastoma (EUNB) protocol is still to be clarified, while, for other group of patients, the presence of SCAs is associated with poor prognosis.Methods:To understand the role of SCAs we performed multilocus/pangenomic analysis of 98 tumour samples from patients enrolled in the EUNB protocol.Results:Age at diagnosis was categorised into two groups using 18 months as the age cutoff. Significant difference in the presence of SCAs was seen in tumours of patients between 12 and 18 months and over 18 months of age at diagnosis, respectively (P=0.04). A significant correlation (P=0.03) was observed between number of SCAs per tumour and age. Event-free (EFS) and overall survival (OS) were calculated in both age groups, according to both the presence and number of SCAs. In older patients, a poorer survival was associated with the presence of SCAs (EFS=46% vs 75%, P=0.023; OS=66.8% vs 100%, P=0.003). Moreover, OS of older patients inversely correlated with number of SCAs (P=0.002). Finally, SCAs provided additional prognostic information beyond histoprognosis, as their presence was associated with poorer OS in patients over 18 months with unfavourable International Neuroblastoma Pathology Classification (INPC) histopathology (P=0.018).Conclusions:The presence of SCAs is a negative prognostic marker that impairs outcome of patients over the age of 18 months with localised unresectable NB without MYCN amplification, especially when more than one SCA is present. Moreover, in older patients with unfavourable INPC tumour histoprognosis, the presence of SCAs significantly affects OS. [ABSTRACT FROM AUTHOR]

Post-transplant lymphoproliferative disease (PTLD) is the most frequent malignant complication of transplantation in childhood. Even with modern post-transplant immunosuppressive strategies, 1-2 % of all kidney transplant recipients will develop PTLD within the first 5 years after transplantation, and the risk remains high even thereafter as long as immunosuppression is required. In addition to PTLD, adult kidney transplant recipients have an increased incidence of other immunosuppression-related malignancies, such as non-melanoma skin cancer or Kaposi's sarcoma. It is foreseeable that pediatric transplant recipients will face similar complications during their adult life. Not only immunosuppression but also other risk factors have been identified for some of these malignancies. Strategies addressing these risk factors during childhood may contribute to life-long cancer prevention. Furthermore, early recognition and regular screening may facilitate early diagnosis and treatment, thereby reducing transplant-related morbidity. In this review we focus on malignant complications after renal transplantation and discuss known risk factors. We also review current screening strategies for malignancies during post-transplant follow-up. [ABSTRACT FROM AUTHOR]

Introduction Neuroblastoma is one of the commonest and deadliest forms of childhood cancer and major initiatives are ongoing to improve the outcome of these patients. Sources of data Data for this review were obtained from PubMed and abstracts from the American Society of Clinical Oncology and Advances in Neuroblastoma Research. Areas of agreement Collaborative clinical trials have led to major improvements in treatment outcomes for low and intermediate risk neuroblastoma, and international initiatives such as the International Neuroblastoma Risk Group have produced a very refined risk stratification incorporating clinical and biological risk factors. Areas of controversy Despite many efforts, the outcome for high-risk neuroblastoma is still poor and the only new strategy incorporated into frontline treatment is anti-GD2 immunotherapy. It is unclear how new drugs targeting specific molecular aberrations will be incorporated. Growing points Genomic characterization and drug development have undergone major advances in the last 5 years leading to a much deeper understanding of tumour biology as well as active biomarker-driven preclinical and clinical research on new molecules that will hopefully progress faster and more efficiently into frontline combination treatment strategies. Areas timely for developing research Significant effort remains to be done in integrating the different new strategies, combining new molecularly targeted agents to maximize therapeutic benefit and incorporate immunotherapy together with targeted therapies. [ABSTRACT FROM AUTHOR]

Neuroblastoma (NB) is one of the most common malignant solid tumors in childhood, which derives from the sympathoadrenal lineage of the neural crest and exhibits extremely heterogeneous biological and clinical behaviors. The infant patients frequently undergo spontaneous regression even with metastatic disease, whereas the patients of more than one year of age who suffer from disseminated disease have a poor outcome despite intensive multimodal treatment. Spontaneous regression in favorable NBs has been proposed to be triggered by nerve growth factor (NGF) deficiency in the tumor with NGF dependency for survival, while aggressive NBs have defective apoptotic machinery which enables the tumor cells to evade apoptosis and confers the resistance to treatment. This paper reviews the molecules and pathways that have been recently identified to be involved in apoptotic cell death in NB and discusses their potential prospects for developing more effective therapeutic strategies against aggressive NB. [ABSTRACT FROM AUTHOR]

Background: Neuroblastoma is the most common pediatric solid tumor. About fifty percent of high risk patients die despite treatment making the exploration of new and more effective strategies for improving stratification mandatory. Hypoxia is a condition of low oxygen tension occurring in poorly vascularized areas of the tumor associated with poor prognosis. We had previously defined a robust gene expression signature measuring the hypoxic component of neuroblastoma tumors (NB-hypo) which is a molecular risk factor. We wanted to develop a prognostic classifier of neuroblastoma patients' outcome blending existing knowledge on clinical and molecular risk factors with the prognostic NB-hypo signature. Furthermore, we were interested in classifiers outputting explicit rules that could be easily translated into the clinical setting. Results: Shadow Clustering (SC) technique, which leads to final models called Logic Learning Machine (LLM), exhibits a good accuracy and promises to fulfill the aims of the work. We utilized this algorithm to classify NB-patients on the bases of the following risk factors: Age at diagnosis, INSS stage, MYCN amplification and NBhypo. The algorithm generated explicit classification rules in good agreement with existing clinical knowledge. Through an iterative procedure we identified and removed from the dataset those examples which caused instability in the rules. This workflow generated a stable classifier very accurate in predicting good and poor outcome patients. The good performance of the classifier was validated in an independent dataset. NB-hypo was an important component of the rules with a strength similar to that of tumor staging. Conclusions: The novelty of our work is to identify stability, explicit rules and blending of molecular and clinical risk factors as the key features to generate classification rules for NB patients to be conveyed to the clinic and to be used to design new therapies. We derived, through LLM, a set of four stable rules identifying a new class of poor outcome patients that could benefit from new therapies potentially targeting tumor hypoxia or its consequences. [ABSTRACT FROM AUTHOR]

Neuroblastoma is a genetically and clinically heterogeneous tumor of childhood, arising from precursor cells of the sympathetic nervous system. It is still a challenging cancer for pediatric oncology, as some tumors will spontaneously regress, while others will become refractory to all forms of therapy. The clinical course of this disease is greatly influenced by both patient age and the genetic abnormalities that occur within the tumors. MYCN (v-myc myelocytomatosis viral related oncogene, neuroblastoma derived (avian)) amplification and loss of chromosome 11q heterozygosity have been known to be indicative of poor prognosis. In this article, we review how mutations and structural alterations in specific genes contribute to inheritable predisposition to neuroblastoma and/or to aggressive disease pathogenesis, as well as implications for diagnosis and therapy. These genes include PHOX2B (paired-like homeobox 2b), ALK (anaplastic lymphoma receptor tyrosine kinase), and ATRX (alpha thalassemia/mental retardation syndrome X-linked). [ABSTRACT FROM AUTHOR]