MYCN Status Research Articles

Multiplexed Quantification of Four Neuroblastoma DNA Targets in a Single Droplet Digital PCR Reaction

The detection and characterization of cell-free DNA (cfDNA) in peripheral blood from neuroblastoma patients may serve as a minimally invasive approach to liquid biopsy. Major challenges in the analysis of cfDNA purified from blood samples are small sample volumes and low cfDNA concentrations. Droplet digital PCR (ddPCR) is a technology suitable for analyzing low levels of cfDNA. Reported here are two quadruplexed ddPCR assay protocols that reliably quantify MYCN and ALK copy numbers in a single reaction together with the two reference genes, NAGK and AFF3, and accurately estimate ALKF1174L (exon 23 position 3522, C>A) and ALKR1275Q (exon 25 position 3824, G>A) mutant allele fractions using cfDNA as input. The separation of positive and negative droplets was optimized for detecting two targets in each ddPCR fluorescence channel by the adjustment of the probe and primer concentrations of each target molecule. The quadruplexed assays were validated using a panel of 10 neuroblastoma cell lines and paired blood plasma and primary neuroblastoma samples from nine patients. Accuracy and sensitivity thresholds in quadruplexed assays corresponded well with those from the respective duplexed assays. Presented are two robust quadruplexed ddPCR protocols applicable in the routine clinical setting and that require only minimal plasma volumes for the assessment of MYCN and ALK oncogene status.

Abstract 1729: Novel liposomal topotecan formulation has a lower IC50 than the free form on neuroblastoma cells

Abstract Introduction: Neuroblastomas (NB) are the most common solid tumor in children and infants, and are frequently resistant to all standard therapies. Patients are accordingly vulnerable to acute and long-term systemic effects of toxic chemotherapy. These drugs target rapidly dividing cells throughout the body, leading to severe side effects. One strategy to reduce off-target toxicities is to selectively increase drug uptake in the tumor. In pilot studies, we found that microbubbles containing liposomal doxorubicin, an agent that is effective against NB, and focused ultrasound (sonoporation) increased doxorubicin uptake in NB xenografts. However, NB is typically treated with multidrug chemotherapy, raising the importance of testing additional agents. In these studies, we evaluated a novel liposomal formulation of topotecan, an agent used in NB treatment which is both effective and associated with significant systemic toxicities. In vitro studies are needed to determine the IC50 (concentration of the drug needed to reduce the number of live cells by half). A required esterase cleavage at the delivery site can inhibit liposome encapsulated drug release. Therefore, we hypothesized that liposomal topotecan (2T-T) would have a higher IC50 than free topotecan. Methods: We tested the effect of 2T-T on nine different NB cell lines:LA1-55n, LA-1-5S, LAN-5, NGP, SK-N-AS, BE2, SHEP, NBL-WN, and SH-SY5Y;five N-type (invasive), three S-type (noninvasive), seven MYCN-amplified (poor prognosis). We have tested free topotecan in 3 of these (LA-1-5S, NBL-WN, SH-SY5Y). Cells were plated in full RPMI at 80% confluence. 2T-T or topotecan (0 to 50 uM) were added to cells 24 hours later for 72 hours. Viable cells were estimated using a WST cell counting kit. 50uM empty liposomes and lysis buffer were used as controls. Experiments were performed in triplicate, with p≥0.05deemed significant (student t-test or ratio-paired t-test using PRISM). Results: 2T-T had a mean IC50 of 0.37±0.58uM(mean R2=0.9±0.07).Empty liposomes caused no cytotoxicity in any cell line. We found no difference in IC50 according to S or N type (0.50±0.65vs 0.35±0.58(p=ns)). The mean IC50 of MYCN-amplified cells was 0.47±0.63,while that of non-MYCN-amplified was 0.031±0.029(n=2), suggesting no difference in cytotoxicity based on MYCN status. 2T-T had a 2 fold lower IC50 than free topotecan (1.14±1.19vs 0.48±0.82,p=0.046), suggesting liposomes did not inhibit topotecan release. Conclusion: These findings suggest that liposomal topotecan (T2-T) has a lower IC50 than free topotecan in NB, and that MYCN amplification and phenotype do not modify 2T-T cytotoxicity. Our results suggest that liposomal encapsulation does not inhibit topotecan release, but could increase its cytotoxicity by increasing topotecan half-life. We predict that, in vivo 2T-T could reduce toxicities and side effects, warranting the investigation of 2T-T sonoporation in NB xenografts. Citation Format: Paula Viza Gomes, Stephanie Shen, Meghan Hill, Kilkee Flynn, Mendi Marquez, Liliya Frolova, Jessica J. Kandel, Michaelann Tartis, Sonia L. Hernandez. Novel liposomal topotecan formulation has a lower IC50 than the free form on neuroblastoma cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1729.

Abstract B30: ARID1A is a haploinsufficient tumor suppressor for N-Myc transformation of neural crest cells

Abstract Large segmental chromosomal alterations are common to cancer and a feature of high-risk neuroblastoma (NBL). Though they are early or initiating events in cancer, including often being found in precancerous lesions, their contribution to tumorigenesis is poorly understood. An unproven model is that these changes promote cancer through the cumulative effect of multiple dosage-sensitive genes. Loss of heterozygosity (LOH) at 1p36 is a frequent structural rearrangement in a broad range of human cancers including NBL. Approximately 70% of MYCN amplified NBL have 1p36 LOH with both mutations independently contributing to tumor aggressiveness in NBL. Two tumor suppressor regions have been proposed to exist in 1p36, a distal and proximal region, which have MYCN-independent and dependent roles. Through CRISPR/Cas9 genome editing of primary mouse neural crest cells (NCCs), a source for NBL, we found that loss of the chromatin remodeling factor Chd5 conferred most of the tumor-suppressor effects of 1p36 LOH in in vitro cell transformation assays in cells with endogenous levels of N-Myc. In contrast, when N-Myc was overexpressed, tumor evolution of NCCs genome edited to have randomly sized 1p36 deletions showed a reduction in tumor latency that significantly correlated with deletion of Arid1a. The Arid1a deletions that were selected for ranged from small indels up to large 1p36 deletions, indicating that large deletions are tolerated to achieve loss of a single critical tumor suppressor. Further, using lentiviral Cre-induced deletion of floxed Arid1a in isolated NCCs, we found that Arid1a is a haploinsufficient tumor suppressor in MYCN-driven transformation of NCCs. As Arid1a is a subunit of the chromatin remodeling complex SWI/SNF, which is mutated in 20% of cancers, Arid1a synthetic lethal therapies are being developed for adult malignancies. We are currently verifying those proposed therapies in NBL and are using small-molecule screening of cells lines derived from Arid1a wild-type, het, or null tumors to identify additional synthetic lethalities. Our findings indicate that context, such as the status of MYCN as an oncogene, dictates which 1p36 gene is the critical tumor suppressor, establishing 1p36 LOH as multifaceted not cumulative, as was previously believed. Citation Format: Kirby Wallace, Jesus Garcia-Lopez, Joel Otero, Rachelle Olsen, Chelsea DeVaux, Ashton King, Andrew Davidoff, Kevin Freeman. ARID1A is a haploinsufficient tumor suppressor for N-Myc transformation of neural crest cells [abstract]. In: Proceedings of the AACR Special Conference on the Advances in Pediatric Cancer Research; 2019 Sep 17-20; Montreal, QC, Canada. Philadelphia (PA): AACR; Cancer Res 2020;80(14 Suppl):Abstract nr B30.

Exploration of the molecular characteristics of the tumor-immune interaction and the development of an individualized immune prognostic signature for neuroblastoma.

Neuroblastoma (NBL) exists in a complex tumor-immune microenvironment. Immune cell infiltration and tumor-immune molecules play a critical role in tumor development and significantly impact the prognosis of patients. However, the molecular characteristics describing the NBL-immune interaction and their prognostic potential have yet to be investigated systematically. We first employed multiple machine learning algorithms, such as Gene Sets Enrichment Analysis and cell type identification by estimating relative subsets of RNA transcripts, to identify immunophenotypes and immunological characteristics in NBL patient data from public databases and then investigated the prognostic potential and regulatory networks of identified immune-related genes involved in the NBL-immune interaction. The immunity signature combining nine immunity genes was confirmed as more effective for individual risk stratification and survival outcome prediction in NBL patients than common clinical characteristics (area under the curve [AUC] = 0.819, C-index = 0.718, p < .001). A mechanistic exploration revealed the regulatory network of molecules involved in the NBL-immune interaction. These immune molecules were also discovered to possess a significant correlation with plasma cell infiltration, MYCN status, and the level of chemokines and macrophage-related molecules (p < .001). A nomogram was constructed based on the immune signature and clinical characteristics, which showed high potential for prognosis prediction (AUC = 0.856, C-index = 0.755, p < .001). We systematically elucidated the complex regulatory mechanisms and characteristics of the molecules involved in the NBL-immune interaction and their prognostic potential, which may have important implications for further understanding the molecular mechanism of the NBL-immune interaction and identifying high-risk NBL patients to guide clinical treatment.

Beyond the Warburg Effect: N-Myc Contributes to Metabolic Reprogramming in Cancer Cells.

Cancer cells generate large amounts of lactate derived from glucose regardless of the available oxygen level. Cancer cells finely control ATP synthesis by modulating the uptake of substrates and the activity of enzymes involved in aerobic glycolysis (Warburg effect), which enables them to adapt to the tumor microenvironment. However, increasing evidence suggests that mitochondrial metabolism, including the tricarboxylic acid (TCA) cycle, oxidative phosphorylation (OXPHOS), and glutaminolysis, is paradoxically activated in MYCN-amplified malignancies. Unlike non-amplified cells, MYCN-amplified cancer cells significantly promote OXPHOS-dependent ATP synthesis. Furthermore, tumor cells are differentially dependent on fatty acid β-oxidation (FAO) according to N-Myc status. Therefore, upregulation of FAO-associated enzymes is positively correlated with both N-Myc expression level and poor clinical outcome. This review explores therapeutic strategies targeting cancer stem-like cells for the treatment of tumors associated with MYCN amplification.

ATR Inhibition Potentiates PARP Inhibitor Cytotoxicity in High Risk Neuroblastoma Cell Lines by Multiple Mechanisms.

Background: High risk neuroblastoma (HR-NB) is one the most difficult childhood cancers to cure. These tumours frequently present with DNA damage response (DDR) defects including loss or mutation of key DDR genes, oncogene-induced replication stress (RS) and cell cycle checkpoint dysfunction. Aim: To identify biomarkers of sensitivity to inhibition of Ataxia telangiectasia and Rad3 related (ATR), a DNA damage sensor, and poly (ADP-ribose) polymerase (PARP), which is required for single strand break repair. We also hypothesise that combining ATR and PARP inhibition is synergistic. Methods: Single agent sensitivity to VE-821 (ATR inhibitor) and olaparib (PARP inhibitor), and the combination, was determined using cell proliferation and clonogenic assays, in HR-NB cell lines. Basal expression of DDR proteins, including ataxia telangiectasia mutated (ATM) and ATR, was assessed using Western blotting. CHK1S345 and H2AXS129 phosphorylation was assessed using Western blotting to determine ATR activity and RS, respectively. RS and homologous recombination repair (HRR) activity was also measured by γH2AX and Rad51 foci formation using immunofluorescence. Results: MYCN amplification and/or low ATM protein expression were associated with sensitivity to VE-821 (p < 0.05). VE-821 was synergistic with olaparib (CI value 0.04–0.89) independent of MYCN or ATM status. Olaparib increased H2AXS129 phosphorylation which was further increased by VE-821. Olaparib-induced Rad51 foci formation was reduced by VE-821 suggesting inhibition of HRR. Conclusion: RS associated with MYCN amplification, ATR loss or PARP inhibition increases sensitivity to the ATR inhibitor VE-821. These findings suggest a potential therapeutic strategy for the treatment of HR-NB.

Age, Diagnostic Category, Tumor Grade, and Mitosis-Karyorrhexis Index Are Independently Prognostic in Neuroblastoma: An INRG Project.

The Children's Oncology Group (COG) stratifies the treatment of patients with neuroblastoma on the basis of a combination of biomarkers that include age and tumor histology classified by age-linked International Neuroblastoma Pathology Classification (INPC) criteria. By definition, this leads to a duplication of the prognostic contribution of age. The individual histologic features underlying the INPC have prognostic strength and are incorporated in the International Neuroblastoma Risk Group classification schema. Here, we analyzed data in the International Neuroblastoma Risk Group Data Commons to validate the prognostic strength of the underlying INPC criteria and to determine whether a risk classification devoid of the confounding of age and INPC criteria will identify new prognostic subgroups. Event-free survival of patients diagnosed between 1990 and 2002 (cohort 1; n = 10,104) and between 2003 and 2016 (cohort 2; n = 8,761) was analyzed. Recursive partitioning with univariate Cox models of event-free survival ("survival tree regression") was performed using (1) individual INPC criteria (age at diagnosis, histologic category, mitosis-karyorrhexis index (MKI), grade of differentiation) and (2) factors in (1) plus other COG-risk biomarkers (International Neuroblastoma Staging System [INSS] stage, MYCN status, ploidy). The independent prognostic ability of age, histologic category, MKI, and grade were validated. Four histologic prognostic groups were identified (< 18 months with low v high MKI, and ≥ 18 months with differentiating v undifferentiated/poorly differentiating tumors). Compared with survival trees generated with established COG risk criteria, an additional prognostic subgroup was identified and validated when individual histologic features were analyzed in lieu of INPC. Replacing INPC with individual histologic features in the COG risk classification will eliminate confounding, facilitate international harmonization of risk classification, and provide a schema for more precise prognostication and refined therapeutic approaches.

Low DLG2 gene expression, a link between 11q-deleted and MYCN-amplified neuroblastoma, causes forced cell cycle progression, and predicts poor patient survival

BackgroundNeuroblastoma (NB) is a childhood neural crest tumor. There are two groups of aggressive NBs, one with MYCN amplification, and another with 11q chromosomal deletion; these chromosomal aberrations are generally mutually exclusive. The DLG2 gene resides in the 11q-deleted region, thus makes it an interesting NB candidate tumor suppressor gene.MethodsWe evaluated the association of DLG2 gene expression in NB with patient outcomes, stage and MYCN status, using online microarray data combining independent NB patient data sets. Functional studies were also conducted using NB cell models and the fruit fly.ResultsUsing the array data we concluded that higher DLG2 expression was positively correlated to patient survival. We could also see that expression of DLG2 was inversely correlated with MYCN status and tumor stage. Cell proliferation was lowered in both 11q-normal and 11q-deleted NB cells after DLG2 over expression, and increased in 11q-normal NB cells after DLG2 silencing. Higher level of DLG2 increased the percentage of cells in the G2/M phase and decreased the percentage of cells in the G1 phase. We detected increased protein levels of Cyclin A and Cyclin B in fruit fly models either over expressing dMyc or with RNAi-silenced dmDLG, indicating that both events resulted in enhanced cell cycling. Induced MYCN expression in NB cells lowered DLG2 gene expression, which was confirmed in the fly; when dMyc was over expressed, the dmDLG protein level was lowered, indicating a link between Myc over expression and low dmDLG level.ConclusionWe conclude that low DLG2 expression level forces cell cycle progression, and that it predicts poor NB patient survival. The low DLG2 expression level could be caused by either MYCN-amplification or 11q-deletion.Graphical abstract7SyKbbVmZCgRq79fyZHmzkVideo

MTHFR and VDR Polymorphisms Improve the Prognostic Value of MYCN Status on Overall Survival in Neuroblastoma Patients.

Single nucleotide polymorphisms (SNPs) in Pharmacogenetics can play an important role in the outcomes of the chemotherapy treatment in Neuroblastoma, helping doctors maximize efficacy and minimize toxicity. Employing AgenaBioscience MassArray, 96 SNPs were genotyped in 95 patients looking for associations of SNP with response to induction therapy (RIT) and grade 3–4 toxicities, in High Risk patients. Associations of SNPs with overall (OS) and event-free (EFS) survival in the whole cohort were also explored. Cox and logistic regression models with Elastic net penalty were employed. Association with grade 3–4 gastrointestinal and infectious toxicities was found for 8 different SNPs. Better RIT was correlated with rs726501 AG, rs3740066 GG, rs2010963 GG and rs1143684 TT (OR = 2.87, 1.79, 1.23, 1.14, respectively). EFS was affected by rs2032582, rs4880, rs3814058, rs45511401, rs1544410 and rs6539870. OS was influenced by rs 1801133, rs7186128 and rs1544410. Remarkably, rs1801133 in MTHFR (p = 0.02) and rs1544410 in VDR (p = 0.006) also added an important predictive value for OS to the MYCN status, with a more accurate substratification of the patients. Although validation studies in independent cohorts will be required, the data obtained supports the utility of Pharmacogenetics for predicting Neuroblastoma treatment outcomes.

Cellular components in tumor microenvironment of neuroblastoma and the prognostic value.

BackgroundTumor microenvironment (TME) contributes to tumor development, progression, and treatment response. In this study, we detailed the cell composition of the TME in neuroblastoma (NB) and constructed a cell risk score model to predict the prognosis of NB.MethodsxCell score was calculated through transcriptomic data from the datasets GSE49711 and GSE45480 based on the xCell algorithm. The random forest method was employed to select important features and the coefficient was obtained via multivariate cox regression analysis to construct a prognostic model, and the performance was validated in another two independent datasets, GSE16476 and TARGET-NBL.ResultsWe found that both immune and non-immune cells varies significantly in different prognostic groups, and were correlated with survival time. The proposed prognostic cell risk score (pCRS) model we constructed can be an independent prognostic indicator for overall survival (OS) and event-free survival (EFS) (training: OS, HR 1.579, EFS, HR 1.563; validation: OS, HR 1.665, 3.848, EFS, HR 2.203, all p-values < 0.01) and only independent prognostic factor in International Neuroblastoma Risk Group high risk patients (HR 1.339, 3.631; p-value 1.76e–2, 3.71e–5), rather than MYCN amplification. Besides, pCRS model showed good performance in grouping, in discriminating MYCN status, the area under the curve (AUC) was 0.889, 0.933, and 0.861 in GSE49711, GSE45480, and GSE16476, respectively. In separating high risk groups, the AUC was 0.904 in GSE49711.ConclusionThis study details the cellular components in the TME of NB through gene expression data, the proposed pCRS model might provide a basis for treatment selection of high risk patients or targeting cellular components of TME in NB.

Systematic computational identification of prognostic cytogenetic markers in neuroblastoma

BackgroundNeuroblastoma (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.MethodsFirst, 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.ResultsHere, 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.ConclusionOur 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.

Telomerase Is a Prognostic Marker of Poor Outcome and a Therapeutic Target in Neuroblastoma.

Telomere maintenance is a hallmark of high-risk neuroblastoma; however, the contribution of telomerase and alternative lengthening of telomeres (ALT) to clinical phenotypes has remained unclear. We aimed to determine the clinical relevance of telomerase activation versus ALT as biomarkers in pretreatment neuroblastoma and to assess the potential value of telomerase as a therapeutic target. The genomic status of TERT and MYCN was assessed in 457 pretreatment neuroblastomas by fluorescence in situ hybridization. ALT was examined in 273 of 457 tumors by detection of ALT-associated promyelocytic leukemia nuclear bodies, and TERT expression was determined by microarrays in 223 of these. Cytotoxic effects of telomerase-interacting compounds were analyzed in neuroblastoma cell lines in vitro and in vivo. We detected TERT rearrangements in 46 of 457 cases (10.1%), MYCN amplification in 93 of 457 cases (20.4%), and elevated TERT expression in tumors lacking TERT or MYCN alterations in 10 of 223 cases (4.5%). ALT activation was found in 49 of 273 cases (17.9%). All these alterations occurred almost mutually exclusively and were associated with unfavorable prognostic variables and adverse outcome. The presence of activated telomerase (ie, TERT rearrangements, MYCN amplification, or high TERT expression without these alterations) was associated with poorest overall survival and was an independent prognostic marker in multivariable analyses. We also found that the telomerase-interacting compound 6-thio-2'-deoxyguanosine effectively inhibited viability and proliferation of neuroblastoma cells bearing activated telomerase. Similarly, tumor growth was strongly impaired upon 6-thio-2'-deoxyguanosine treatment in telomerase-positive neuroblastoma xenografts in mice. Our data suggest telomerase activation and ALT define distinct neuroblastoma subgroups with adverse outcome and that telomerase may represent a promising therapeutic target in many high-risk neuroblastomas.

The targetable kinase PIM1 drives ALK inhibitor resistance in high-risk neuroblastoma independent of MYCN status

Resistance to anaplastic lymphoma kinase (ALK)-targeted therapy in ALK-positive non-small cell lung cancer has been reported, with the majority of acquired resistance mechanisms relying on bypass signaling. To proactively identify resistance mechanisms in ALK-positive neuroblastoma (NB), we herein employ genome-wide CRISPR activation screens of NB cell lines treated with brigatinib or ceritinib, identifying PIM1 as a putative resistance gene, whose high expression is associated with high-risk disease and poor survival. Knockdown of PIM1 sensitizes cells of differing MYCN status to ALK inhibitors, and in patient-derived xenografts of high-risk NB harboring ALK mutations, the combination of the ALK inhibitor ceritinib and PIM1 inhibitor AZD1208 shows significantly enhanced anti-tumor efficacy relative to single agents. These data confirm that PIM1 overexpression decreases sensitivity to ALK inhibitors in NB, and suggests that combined front-line inhibition of ALK and PIM1 is a viable strategy for the treatment of ALK-positive NB independent of MYCN status.

Impact of MYCN status on response of high-risk neuroblastoma to neoadjuvant chemotherapy

Background/PurposeMYCN-amplification in neuroblastoma is associated with an aggressive clinical phenotype. We evaluated the association of MYCN amplification with tumor response to neoadjuvant chemotherapy. MethodsPrimary tumor response, assessed by percentage volume change on CT scan and degree of tumor resection, assessed by the operating surgeon, were retrospectively compared in 84 high-risk neuroblastoma patients. There were thirty-four (40%) with MYCN-amplified tumors and fifty (60%) with non-amplified tumors treated at our institution from 1999 to 2016. Metastatic disease response was assessed on MIBG scan by change in Curie score. ResultsMYCN-amplification was associated with a greater mean percentage reduction in primary tumor volume after neoadjuvant chemotherapy (72.27% versus 46.83% [non-amplified tumors], p = 0.001). The percentage of patients with a Curie score > 2 at diagnosis who then had a score ≤ 2 after neoadjuvant chemotherapy was not significantly different (8 [61.5%] and 8 [34.8%], respectively, p = 0.37). Twenty-eight (85.7%) patients with MYCN-amplification had ≥90% surgical resection compared to 45 (91.84%) patients with non-amplified tumors (p = 0.303). ConclusionsMYCN-amplification in high-risk neuroblastoma was associated with a better response of the primary tumor to neoadjuvant chemotherapy, but not metastatic sites, than in patients with non-amplified tumors. This did not significantly impact the ability to resect ≥90% of the primary tumor/locoregional disease. Type of StudyTreatment Study Level of EvidenceLevel III

Unfavorable Outcome of Neuroblastoma in Patients With 2p Gain.

Background: Amplification of the MYCN oncogene is the most unfavorable genetic factor in neuroblastoma patients. However, knowledge about the clinical impact of low-level multiplication of MYCN is still insufficient. Therefore, we aimed to investigate the disease course in patients with different copy number status of MYCN.Materials and Methods: We examined 105 children diagnosed with neuroblastoma from 2010 to 2018 in five pediatric oncology centers in Poland. We determined the MYCN status at diagnosis by the interphase FISH examination and assessed the clinical outcome in patients.Results: A total of 35% of tumors presented with chromosome 2 numerical changes, 20% had MYCN amplification and 16% revealed 2p gain. Unexpectedly, we observed very low overall survival and event free survival (EFS) rates in neuroblastomas with 2p gain, which were comparable with patients with MYCN amplification.Conclusions: The 2p gain alteration should be reported as a strong unfavorable prognostic marker in neuroblastoma patients.

Association of image-defined risk factors, tumor resectability, and prognosis in children with localized neuroblastoma.

Although localized neuroblastoma has a good prognosis, some cases have undergone treatment failure or recurrence. Apart from biologic features such as MYCN status, we wondered whether some characteristics of growing tumors are prognostic, such as a well-encapsulated mass without infiltration of vital organs. We analyzed the diagnostic utility of image-defined risk factors (IDRFs) to predict successful treatment and prognosis. The overall goal was to achieve maximum cure rates for patients with localized neuroblastoma through a better understanding of clinical characteristics. We retrospectively reviewed the images of patients with localized neuroblastoma who were enrolled between June 1998 and December 2012 at a single institution in Shanghai, China. Unequivocal categorization regarding IDRFs was available in 67 patients. IDRF was assessed at diagnosis and after four cycles of neoadjuvant chemotherapy, on average. The median follow-up period was 84months (range: 48-132months) after diagnosis. MRI and CT indicated a total of 177 IDRFs in these 67 patients. Logistic regression analysis revealed a highly significant negative correlation between the numbers of IDRFs and the possibility of complete removal of neuroblastoma. Intraspinal extension of the tumor, compression of the trachea, and encasement of the main artery in localized neuroblastoma were predictors for incomplete tumor resection. According to univariate analysis, ≥4 IDRFs and intraspinal extension of the tumor were significant indicators of poor prognosis. The number of IDRFs was useful in predicting surgical outcome and event-free survival. The number of IDRFs should be considered in protocol planning, instead of IDRF presence or absence.

A prognostic nomogram for neuroblastoma in children.

IntroductionNeuroblastoma is one of the most common extracranial solid tumors in children, which accounts for about 7–10% in children’s tumors. The prognosis group of patients with neuroblastoma could not only improve the efficacy of high-risk patients, but also reduce the effects of drug complications for surviving patients.Material and MethodsPatients diagnosed with neuroblastoma between 1986 and 2012 were selected form the TARGET database. The nomogram was built with potential risk factors based on COX regression analysis. The precision of the 3-year and 5-year survival of the nomograms was evaluated by the area under receiver operating characteristic (ROC) curve (AUC).ResultsA total of 757 child neuroblastoma patients were selected from the TARGET database. Univariate analysis showed that age of diagnosis (>520 day), race of American Indian or Alaska Native, stage 4 in International Neuroblastoma Staging System (INSS), MYCN status, DNA ploidy, and high mitosis-karyorrhexis index were associated with overall survival (OS). Multivariate analysis showed age of diagnosis (>520 day), stage 4 in INSS and DNA ploidy were independent risk factors of OS. The concordance index (C-index) of the nomogram was 0.704 (95% CI [0.686–0.722]) in the training cohort while the C-index in the validation cohort was 0.672 (95% CI [0.644–0.700]). AUC values of ROC curves for 3-year OS and 5-year OS in the training cohort were 0.732 and 0.772, respectively. The nomogram performed better compared with INSS staging system, tumor histology and children’s oncology group (COG) risk group with C-indexes of 0.662 (95% CI [0.648–0.676]), 0.637 (95% CI [0.622–0.652]) and 0.651 (95% CI [0.637–0.665]), respectively.ConclusionsThe nomogram showed stronger predictive power than the INSS staging system, tumor histology and COG risk group. Precise estimates of the prognosis of childhood neuroblastoma might help doctors make better treatment decisions.

A revised Children's Oncology Group (COG) neuroblastoma risk classification system: Report from the COG biology study ANBL00B1.

10012 Background: The COG risk classification system previously used the International Neuroblastoma Staging System (INSS). The pre-treatment INRG staging system (INRGSS) has been adopted internationally, requiring integration of INRGSS with known prognostic biological and clinical characteristics to evaluate outcomes and assess whether this incorporation will require revision to the established COG risk classifier. Methods: 4,037 newly diagnosed neuroblastoma patients were enrolled on COG ANBL00B1 between 2006-2014. Staging per the INSS and INRGSS was determined. Tumor biological and histologic features, including MYCN status [amplified (A) versus not amplified (NA)], ploidy, histology, and segmental chromosome aberrations (SCA) including 1p and 11q LOH, were assessed centrally. Survival analyses were performed to identify independent prognostic factors and to calculate event-free and overall survival (EFS, OS) for combinations of variables used to determine risk group assignments according to COG and INRG classification templates. Results: Using the original COG risk classifier 1,309 low (LR), 992 intermediate (IR) and 1,736 high-risk (HR) patients were identified with 5-year EFS of 91.4±2.1%, 84.3±2.9%, 45.2±3.1%, and OS of 98.1±1.0%, 94.0±1.9%, 54.1±3.0%, respectively. Outcomes based on combinations of clinical and biological prognostic factors were determined and compared for subsets of patients according to the COG (version1) and INRG risk classification systems to develop a revised COG risk classifier that incorporates the INRGSS (version 2, subset shown in table). Conclusions: Use of INRGSS requires a revision to the COG risk classifier. By combining INRGSS and presence of SCA together with age, MYCN status, ploidy, and histology to determine outcome of patients treated with modern era therapies, we developed a revised risk classification system to inform therapy and COG clinical trial eligibility. Clinical trial information: NCT00904241. [Table: see text]

Poverty and survival in targeted immunotherapy clinical trials.

10034 Background: Whether precision medicine trials—which tailor medical treatment to a patient’s individual tumor characteristics—should include poverty as an outcome predictor is unknown. In Children’s Oncology Group (COG) trials ANBL0032 and ANBL0931, targeted immunotherapy resulted in the single greatest survival improvement for high-risk neuroblastoma (HR NBL) in decades. We utilized the ANBL0032/ANBL0931 cohort to investigate the hypothesis that poverty independently predicts inferior survival outcomes in targeted immunotherapy trials. Methods: We retrospectively analyzed outcome data for patients uniformly treated with immunotherapy on ANBL0032/ANBL0931 at Pediatric Health Information System-associated hospitals. Poverty exposure was a priori characterized at the neighborhood and household level. Neighborhood poverty was defined as living in a ZIP code with a median household income in the cohort’s lowest quartile ( &lt; $35,916 vs. $46,324-$60,947). Household poverty was defined as Medicaid insurance (vs. private/other). Multivariable Cox regression evaluated associations between poverty exposures and event-free (EFS) and overall (OS) survival adjusting for demographic, clinical and tumor variables (ethnicity, hospital clustering, disease response, disease stage, MYCN status). Post-hoc analyses examined the joint effect of neighborhood and household poverty using a common reference. Results: Among 371 patients, 25% lived in high-poverty ZIP codes; 35% were Medicaid-insured; 14% were exposed to both. Only Medicaid was independently associated with inferior EFS (hazard ratio (HR) 1.90, 95% confidence interval (CI) 1.28-2.84, p = 0.001). OS was inferior in children with Medicaid (HR 2.79, 95%CI 1.63-4.79, p &lt; 0.001) and less than complete disease response (HR 1.89, 95%CI 1.004-3.56, p = 0.049). In post-hoc analysis, joint poverty exposure had a more pronounced impact on EFS (HR 2.21, 95%CI 1.48 to 3.30, p &lt; 0.001) and OS (HR 3.7, 95%CI 2.08-6.59, p &lt; 0.001) than Medicaid alone. No other covariate remained significantly associated with survival. Conclusions: Poverty independently predicted inferior EFS and OS among a cohort of neuroblastoma patients uniformly treated with targeted immunotherapy. For the full potential of precision medicine to be realized, future clinical trials should systematically investigate and intervene upon poverty as a significant predictor of survival.

Predicting outcome of neuroblastoma using N-myc status and Trk-A expression

Background: Neuroblastoma is an embryonal cancer of the postganglionic sympathetic nervous system. It is the third most common pediatric cancer. The aim of the present study was to determine MYCN amplification and Trk-A expression in tissue samples of neuroblastoma cases and to correlate them with clinical status, stage and histopathology of the disease.Methods: This prospective study was conducted at the Institute of Child Health and hospital for children [ICH &amp; HC], Egmore during the period from June 2011 to March 2012. Ten children of age between 8 months to 12 years diagnosed with neuroblastoma were included in the study. Tissue samples were collected from all patients and sent to evaluate histopathology to confirm the presence of neuroblastoma. Gene expression was studied using TaqMan quantitative RT-PCR. Immunohistochemistry of tissues samples were done to evaluate N-myc amplification and Trk A expression.Results: The most common presenting symptom was mass in the abdomen (60%) in the patients. In majority, stage 3 neuroblastoma was noticed in 5 (50%) cases. On histopathology, 2 (20%) cases were identified of ganglioneuro-blastoma, and 8 (80%) cases as neuroblastoma. N-myc was amplified in 3 cases (30%). No amplification was noted in all 3 cases (0%) of stage 1. None of the case in this study group showed Trk-A expression.Conclusions: N-myc amplification was well correlated with the stages of neuroblastoma. It should be considered to be as an important prognostic marker to select appropriate treatment in children with neuroblastomas.