Outcomes of children with intermediate-risk neuroblastoma after treatment stratified by MYCN status and tumor cell ploidy

Impact of risk-based therapy on late morbidity and mortality in neuroblastoma survivors: a report from the Childhood Cancer Survivor Study

BACKGROUND

Early efforts at risk-adapted therapy for neuroblastoma are predicted to result in differential late effects; the magnitude of these differences has not been well described.

METHODS

Late mortality, subsequent malignant neoplasms (SMNs), and severe/life-threatening chronic health conditions (CHCs), graded according to CTCAE v4.03, were assessed among 5-year Childhood Cancer Survivor Study (CCSS) survivors of neuroblastoma diagnosed 1987-1999. Using age, stage at diagnosis, and treatment, survivors were classified into risk groups (low [n = 425]; intermediate [n = 252]; high [n = 245]). Standardized mortality ratios (SMRs) and standardized incidence ratios (SIRs) of SMNs were compared with matched population controls. Cox regression models estimated hazard ratios (HRs) and 95% confidence intervals for CHC compared with 1029 CCSS siblings.

RESULTS

Among survivors (49.8% male; median age = 21 years, range = 7-42; median follow-up = 19.3 years, range = 5-29.9), 80% with low-risk disease were treated with surgery alone, whereas 79.1% with high-risk disease received surgery, radiation, chemotherapy ± autologous stem cell transplant (ASCT). All-cause mortality was elevated across risk groups (SMRhigh = 27.7 [21.4-35.8]; SMRintermediate = 3.3 [1.7-6.5]; SMRlow = 2.8 [1.7-4.8]). SMN risk was increased among high- and intermediate-risk survivors (SIRhigh = 28.0 [18.5-42.3]; SIRintermediate = 3.7 [1.2-11.3]) but did not differ from the US population for survivors of low-risk disease. Compared with siblings, survivors had an increased risk of grade 3-5 CHCs, particularly among those with high-risk disease (HRhigh = 16.1 [11.2-23.2]; HRintermediate = 6.3 [3.8-10.5]; HRlow = 1.8 [1.1-3.1]).

CONCLUSION

Survivors of high-risk disease treated in the early days of risk stratification carry a markedly elevated burden of late recurrence, SMN, and organ-related multimorbidity, whereas survivors of low/intermediate-risk disease have a modest risk of late adverse outcomes.

Stage 4N neuroblastoma before and during the era of anti-GD2 immunotherapy

Patients with stage 4N neuroblastoma (distant metastases limited to lymph nodes) stand out as virtually the only survivors of high-risk neuroblastoma (HR-NB) before myeloablative therapy (MAT) and immunotherapy with anti-GD2 monoclonal antibodies (mAbs) became standard. Because no report presents more recent results with 4N, we analyzed our large 4N experience. All 51 pediatric 4N patients (<18 years old) diagnosed 1985 to 2021 were reviewed. HR-NB included MYCN-nonamplified 4N diagnosed at age ≥18 months and MYCN-amplified 4N. Among 34 MYCN-nonamplified high-risk patients, 20 are relapse-free 1.5+ to 37.5+ (median 12.5+) years post-diagnosis, including 13 without prior MAT and 5 treated with little (1 cycle; n = 2) or no mAb (n = 3), while 14 patients (7 post-MAT, 8 post-mAbs) relapsed (all soft tissue). Of 15 MYCN-amplified 4N patients, 7 are relapse-free 2.1+ to 26.4+ (median 11.6+) years from the start of chemotherapy (all received mAbs; 3 underwent MAT) and 4 are in second remission 4.2+ to 21.8+ years postrelapse (all soft tissue). Statistical analyses showed no significant association of survival with either MAT or mAbs for MYCN-nonamplified HR-NB; small numbers prevented these analyses for MYCN-amplified patients. The two patients with intermediate-risk 4N (14-months-old) are relapse-free 7+ years postresection of primary tumors; distant disease spontaneously regressed. The natural history of 4N is marked by NB confined to soft tissue without early relapse in bones or bone marrow, where mAbs have proven efficacy. These findings plus curability without MAT, as seen elsewhere and at our center, support consideration of treatment reduction for MYCN-nonamplified 4N.

Development and validation of a 21-gene prognostic signature in neuroblastoma

Survival outcomes for patients with neuroblastoma vary markedly and reliable prognostic markers and risk stratification tools are lacking. We sought to identify and validate a transcriptomic signature capable of predicting risk of mortality in patients with neuroblastoma. The TARGET NBL dataset (n = 243) was used to develop the model and two independent cohorts, E-MTAB-179 (n = 478) and GSE85047 (n = 240) were used as validation sets. EFS was the primary outcome and OS was the secondary outcome of interest for all analysis. We identified a 21-gene signature capable of stratifying neuroblastoma patients into high and low risk groups in the E-MTAB-179 (HR 5.87 [3.83-9.01], p < 0.0001, 5 year AUC 0.827) and GSE85047 (HR 3.74 [2.36-5.92], p < 0.0001, 5 year AUC 0.815) validation cohorts. Moreover, the signature remained independent of known clinicopathological variables, and remained prognostic within clinically important subgroups. Further, the signature was effectively incorporated into a risk model with clinicopathological variables to improve prognostic performance across validation cohorts (Pooled Validation HR 6.93 [4.89-9.83], p < 0.0001, 5 year AUC 0.839). Similar prognostic utility was also demonstrated with OS. The identified signature is a robust independent predictor of EFS and OS outcomes in neuroblastoma patients and can be combined with clinically utilized clinicopathological variables to improve prognostic performance.

Genetic Alterations and Resectability Predict Outcome in Patients with Neuroblastoma Assigned to High-Risk Solely by MYCN Amplification

Simple Summary

Currently, patients with high-risk neuroblastoma are uniformly treated with maximum therapy. This study investigated a high-risk subgroup characterized by the presence of the amplified MYCN oncogene in the tumor regardless of the stage. In contrast to the corresponding high-risk subgroup consisting of patients with metastases and age at diagnosis over 18 months, the investigated subgroup had generally a superior survival chance. However, the detection of mutations of specific genes in the tumor tissue (RAS and p53 pathway including ALK) had a strong, negative impact. These genes should be therefore also investigated in the future. Complete surgical removal of the primary tumor proved to be beneficial for high-risk neuroblastoma patients assigned to the high-risk category solely by MYCN amplification.

Abstract

Background: To identify variables predicting outcome in neuroblastoma patients assigned to the high-risk group solely by the presence of MYCN oncogene amplification (MNA). Methods: Clinical characteristics, genomic information, and outcome of 190 patients solely assigned to high-risk neuroblastoma by MNA were analyzed and compared to 205 patients with stage 4 neuroblastoma aged ≥18 months with MNA (control group). Results: Event-free survival (EFS) and overall survival (OS) at 10 years were 47% (95%-CI 39–54%) and 56% (95%-CI 49–63%), respectively, which was significantly better than EFS and OS of the control group (EFS 25%, 95%-CI 18–31%, p < 0.001; OS 32% 95%-CI 25–39%, p < 0.001). The presence of RAS-/p53-pathway gene alterations was associated with impaired 10-year EFS and OS (19% vs. 55%, and 19% vs. 67%, respectively; both p < 0.001). In time-dependent multivariable analyses, alterations of RAS-/p53-pathway genes and the extent of the best primary tumor resection were the only independent prognostic variables for OS (p < 0.001 and p = 0.011, respectively). Conclusions: Neuroblastoma patients attributed to high risk solely by MYCN amplification have generally a more favorable outcome. Mutations of genes of the RAS and/or p53 pathways and incomplete resection are the main risk factors predicting poor outcome.

Clinical and molecular characterization of patients with stage 4(M) neuroblastoma aged less than 18 months without MYCN amplification

INTRODUCTION

The survival of children with stage 4(M) neuroblastoma without MYCN amplification and below the age of 18 months is considered better than the still dismal outcome of older high-risk neuroblastoma patients. This study analyzes the impact of clinical and molecular characteristics on the long-term outcome.

PATIENTS AND METHODS

Clinical presentation, survival, and recurrence patterns of patients enrolled onto trials NB90, NB97, and NB2004 were retrospectively analyzed. Gene expression signatures based on RNA microarrays (TH10) were investigated if tumor material was available.

RESULTS

Between 1990 and 2015, 177 patients with stage 4(M) MYCN nonamplified neuroblastoma aged less than 18 months at diagnosis were eligible. After a median follow-up of 9.7 years (IQR 5.0, 13.4), the proportions of 10-year event-free survival (EFS) and overall survival (OS) were 73% (95% confidence interval [CI] 67-79%) and 86% (95% CI 80-92%), respectively. Of the 27 neuroblastoma recurrences, 44% occurred in more than one site. Four additional patients presented histologically mature ganglioneuroma at recurrence. Six patients developed a secondary malignancy. The secondary 5-year EFS and OS of the 27 patients with neuroblastoma recurrence were 44% and 59%, respectively. TH10 gene expression signature was not prognostically predictive in the investigated subcohort.

CONCLUSION

The outcome of patients with stage 4(M) neuroblastoma aged less than 18 months is favorable when treated with high-risk or otherwise intensive therapy. The development of secondary malignancies and the potential of maturation to ganglioneuroma call for a controlled stepwise reduction of treatment intensity.

Association Between Participation in Clinical Trials and Overall Survival Among Children With Intermediate- or High-risk Neuroblastoma

IMPORTANCE

Participants in clinical trials may experience benefits associated with new therapeutic strategies as well as tight adherence to best supportive care practices.

OBJECTIVES

To investigate whether participation in a clinical trial is associated with improved survival among children with neuroblastoma and investigate potential recruitment bias of patients in clinical trials.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included pediatric patients with intermediate- or high-risk neuroblastoma in North American studies who were included in the International Neuroblastoma Risk Group Data Commons and who received a diagnosis between January 1, 1991, and March 1, 2020.

EXPOSURE

Enrollment in a clinical trial.

MAIN OUTCOMES AND MEASURES

Event-free survival and overall survival (OS) of patients with intermediate- or high-risk neuroblastoma enrolled in an up-front Children's Oncology Group (COG) clinical trial vs a biology study alone were analyzed using log-rank tests and Cox proportional hazards regression models. The racial/ethnic composition and the demographic characteristics of the patients in both groups were compared.

RESULTS

The cohort included 3058 children with intermediate-risk neuroblastoma (1533 boys [50.1%]; mean [SD] age, 10.7 [14.7] months) and 6029 children with high-risk neuroblastoma (3493 boys [57.9%]; mean [SD] age, 45.8 [37.4] months) who were enrolled in a Children's Oncology Group or legacy group neuroblastoma biology study between 1991 and 2020. A total of 1513 patients with intermediate-risk neuroblastoma (49.5%) and 2473 patients with high-risk neuroblastoma (41.0%) were also enrolled in a clinical trial, for a cohort total of 3986 of 9087 children (43.9%) enrolled in a clinical trial. The prevalence of prognostic markers for the clinical trial and non-clinical trial cohorts differed, although representation of patients from racial/ethnic minority groups was similar in both cohorts. Among patients with intermediate-risk neuroblastoma, OS was higher among those who participated in a clinical trial compared with those enrolled only in a biology study (OS, 95% [95% CI, 94%-96%] vs 91% [95% CI, 89%-94%]; P = .01). Among patients with high-risk neuroblastoma, participation in a clinical trial was not associated with OS (OS, 38% [95% CI, 35%-41%] in the clinical trial group vs 41% [95% CI, 38%-44%] in the biology study group; P = .23).

CONCLUSIONS AND RELEVANCE

Approximately 44% of patients in this large cohort of patients with neuroblastoma were enrolled in up-front clinical trials. Compared with children not enrolled in clinical trials, a higher prevalence of favorable prognostic markers was identified among patients with intermediate-risk neuroblastoma enrolled in clinical trials, and unfavorable features were more prevalent among patients with high-risk neuroblastoma enrolled in clinical trials. No evidence of recruitment bias according to race/ethnicity was observed. Participation in a clinical trial was not associated with OS in this cohort, likely reflecting the common practice of treating nontrial participants with therapeutic and supportive care regimens used in a previous therapeutic trial.

Long-Term Outcome and Role of Biology within Risk-Adapted Treatment Strategies: The Austrian Neuroblastoma Trial A-NB94

Simple Summary

Neuroblastoma, the most common extracranial malignancy of childhood, shows a highly variable course of disease ranging from spontaneous regression or maturation into a benign tumor to an aggressive and intractable cancer in up to 60% of patients. To adapt treatment intensity, risk staging at diagnosis is of utmost importance. The A-NB94 trial was the first in Austria to stratify therapy intensity according to tumor staging, patient’s age, and MYCN amplification status, the latter being a biologic marker turning otherwise low-risk tumors into high-risk disease. Recent publications showed a prognostic impact of various genomic features including segmental chromosomal aberrations (SCAs). We retrospectively investigated the relevance of SCAs within this risk-adapted treatment strategy. The A-NB94 approach resulted in an excellent long-term survival for the majority of patients with acceptable long-term morbidity. An age- and stage-dependent frequency of SCAs was confirmed and SCAs should always be considered in future treatment decision making processes.

Abstract

We evaluated long-term outcome and genomic profiles in the Austrian Neuroblastoma Trial A-NB94 which applied a risk-adapted strategy of treatment (RAST) using stage, age and MYCN amplification (MNA) status for stratification. RAST ranged from surgery only to intensity-adjusted chemotherapy, single or multiple courses of high-dose chemotherapy (HDT) followed by autologous stem cell rescue depending on response to induction chemotherapy, and irradiation to the primary tumor site. Segmental chromosomal alterations (SCAs) were investigated retrospectively using multi- and pan-genomic techniques. The A-NB94 trial enrolled 163 patients. Patients with localized disease had an excellent ten-year (10y) event free survival (EFS) and overall survival (OS) of 99 ± 1% and 93 ± 2% whilst it was 80 ± 13% and 90 ± 9% for infants with stage 4S and for infants with stage 4 non-MNA disease both 83 ± 15%. Stage 4 patients either >12 months or ≤12 months but with MNA had a 10y-EFS and OS of 45 ± 8% and 47 ± 8%, respectively. SCAs were present in increasing frequencies according to stage and age: in 29% of localized tumors but in 92% of stage 4 tumors (p < 0.001), and in 39% of patients ≤ 12 months but in 63% of patients > 12 months (p < 0.001). RAST successfully reduced chemotherapy exposure in low- and intermediate-risk patients with excellent long-term results while the outcome of high-risk disease met contemporary trials.

Norepinephrine-Transporter-Targeted and DNA-Co-Targeted Theranostic Guanidines

High risk neuroblastoma often recurs, even with aggressive treatments. Clinical evidence suggests that proliferative activities are predictive of poor outcomes. This report describes syntheses, characterization, and biological properties of theranostic guanidines that target norepinephrine transporter and undergo intracellular processing, and subsequently their catabolites are efficiently incorporated into DNA of proliferating neuroblastoma cells. Radioactive guanidines are synthesized from 5-radioiodo-2'-deoxyuridine, a molecular radiotherapy platform with clinically proven minimal toxicities and DNA-targeting properties. The transport of radioactive guanidines into neuroblastoma cells is active as indicated by the competitive suppression of cellular uptake by meta-iodobenzylguanidine. The rate of intracellular processing and DNA uptake is influenced by the agent's catabolic stability and cell population doubling times. The radiotoxicity is directly proportional to DNA uptake and duration of exposure. Biodistribution of 5-[¹²⁵I]iodo-3'-O-(ε-guanidinohexanoyl)-2'-deoxyuridine in a mouse neuroblastoma model shows significant tumor retention of radioactivity. Neuroblastoma xenografts regress in response to the clinically achievable doses of this agent.

Defining Risk Factors for Chemotherapeutic Intervention in Infants With Stage 4S Neuroblastoma: A Report From Children's Oncology Group Study ANBL0531

PURPOSE

Infants with stage 4S neuroblastoma usually have favorable outcomes with observation or minimal chemotherapy. However, young infants with symptoms secondary to massive hepatomegaly or with unfavorable tumor biology are at high risk of death. Our aim was to improve outcomes for patients with symptomatic and/or unfavorable biology 4S neuroblastoma with a uniform treatment approach using a biology- and response-based algorithm.

PATIENTS AND METHODS

The subset of patients with 4S disease with MYCN-not amplified tumors with impaired or impending organ dysfunction, or with unfavorable histology and/or diploid DNA index, were eligible. Patients were assigned to receive two, four, or eight cycles of chemotherapy on the basis of histology, diploid DNA index, chromosome arm 1p or 11q loss of heterozygosity (LOH) status, and symptoms.

RESULTS

Forty-nine eligible patients were enrolled: 41 were symptomatic and 28 had unfavorable biology. Seventeen patients (symptomatic, favorable biology) were assigned two cycles, 21 patients (any unfavorable biologic feature without 1p or 11q LOH) were assigned four cycles, and 11 patients (unfavorable biology including 1p and/or 11q LOH [n = 7] or symptomatic with unknown biology [n = 4]), were assigned eight cycles. The 3-year overall survival was 81.4% ± 5.8%. Eight of nine deaths were in patients younger than 2 months of age at diagnosis (median, 9 days [range, 1 to 68 days]): five acute deaths were a result of hepatomegaly and associated toxicities; two were a result of late relapse in patients with unfavorable biology; and two were a result of treatment complications. No deaths occurred after protocol-mandated pre-emptive treatment of infants younger than 2 months with hepatomegaly, regardless of symptoms. A new scoring algorithm for emergent chemotherapy in patients with 4S disease was developed on the basis of this experience.

CONCLUSION

The outcome for 4S neuroblastoma can be improved with pre-emptive chemotherapy for evolving hepatomegaly or other baseline comorbidities in infants younger than 2 months of age.

Analysis of the risk factor for the poor prognosis of localized neuroblastoma after the surgical

Neuroblastoma is a unique malignancy in infants often presenting with either localized or metastatic disease. The study was carried out to explore the risk stratification of the poor prognosis for patients underwent surgical treatment.60 patients diagnosed with neuroblastoma were primarily enrolled in the study from April 2008 to April 2016. All the patients underwent surgical treatment and received 5-year follow-up. Clinical variables, including age, International Neuroblastoma Staging System (INSS) stage, tumor size and site, histology, and MYCN status were retrospectively analyzed, and EFS was chosen as the endpoint.The median age of patients was 8.2 months and average follow-up period was 40.2 ± 8.6 months. Among 60 patients, complete remission was achieved in 35 patients and partial remission in 14 subjects. Poor prognosis including patient death and tumor progression were overserved in 11 patients. Cox multifactor regression analysis revealed that age, histology and MYCN status had significant prognostic effect on event-free survival (EFS) rate for neuroblastoma patients underwent surgical treatment.In our study, we identified a series of prognostic factors including age, histology, and MYCN status predicting the prognosis of neuroblastoma patients after surgical treatment.

Excellent prognosis of patients with intermediate-risk neuroblastoma and residual tumor postchemotherapy

BACKGROUND/PURPOSE

The prognosis of patients with intermediate-risk neuroblastoma is favorable; therefore, a reduction therapy is desired. However, the long-term prognosis of those with residual tumor is unclear. The aim of this study was to clarify the necessity of residual tumor resection.

METHODS

We retrospectively reviewed the records of patients diagnosed with intermediate-risk neuroblastoma who either were treated by chemotherapy only (nonresection group; n=16), or received postchemotherapy tumor resection (resection group; n=9).

RESULTS

In the nonresection group, tumor size decreased in 14 patients; 5 had no detectable local tumor at the end of the follow-up period. Tumor size increased in 2 patients 1.5-2.5years postchemotherapy. Both patients received additional treatment and survived. All patients survived during the median follow-up time of 127months. In the resection group, 5 patients received complete resections and 4 patients received nearly complete resections. All patients survived during the median follow-up time of 84months. In 8 out of 9 resected tumors, regression or maturation was pathologically induced by chemotherapy-only treatment.

CONCLUSION

Patients with intermediate-risk neuroblastoma with or without postchemotherapy residual tumor resection had an excellent long-term outcome. The tumor pathology with intermediate-risk neuroblastoma might be susceptible to change to regression or maturation by chemotherapy.

LEVEL OF EVIDENCE

IV.

Outcomes and complications of surgery in patients with intermediate-risk neuroblastoma: experience from an Indian tertiary Cancer Centre

PURPOSE

The treatment of intermediate risk (IR) neuroblastoma has evolved with the focus now on reducing the drugs, dosage, and duration of chemotherapy. The aim of this study is to present the outcomes of treatment and the complications of surgery in patients with IR neuroblastoma treated at a tertiary cancer center in India.

METHODS

All eligible patients with IR neuroblastoma treated between April 2005 and August 2016 were identified. The presence and number of image-defined risk factors (IDRF) before and after neoadjuvant chemotherapy were retrospectively analyzed as were the extent of surgery, complications, and outcomes.

RESULTS

Of 282 neuroblastoma patients treated during the study period, 54 had IR neuroblastoma. Complete excision was achieved in 25 patients. There were 26 surgical complications in 22 patients with a similar incidence in patients with complete (n = 13) or incomplete (n = 13) resection (p = 0.78). After a median follow-up of 47 months, the 4-year overall and event-free survival was 91.5% and 75%, respectively. There was no difference in survival between patients who underwent complete resection versus those with incomplete resection (p = 0.9).

CONCLUSION

Outcomes of IR neuroblastoma are favorable. The extent of resection does not affect the survival and complications can occur even when the resection is incomplete.

Excellent treatment outcomes in children younger than 18 months with stage 4 MYCN nonamplified neuroblastoma

Purpose

Although the prognosis is generally good in patients with intermediate-risk neuroblastoma, no consensus has been reached on the ideal treatment regimen. This study analyzed treatment outcomes and toxicities in patients younger than 18 months with stage 4 MYCN nonamplified neuroblastoma.

Methods

We retrospectively analyzed 20 patients younger than 18 months newly diagnosed with stage 4 MYCN nonamplified neuroblastoma between January 2009 and December 2015. Patients received 9 cycles of chemotherapy and surgery, with or without local radiotherapy, followed by 12 cycles of differentiation therapy with 13-cis-retinoic acid. Chemotherapy consisted of alternating cycles of cisplatin, etoposide, doxorubicin, and cyclophosphamide (CEDC) and ifosfamide, carboplatin, and etoposide (ICE) regimens.

Results

The most common primary tumor site was the abdomen (85%), and the most common metastatic sites were the lymph nodes (65%), followed by the bones (60%), liver (55%), skin (45%), and bone marrow (25%). At the end of induction therapy, 14 patients (70%) achieved complete response, with 1 achieving very good partial response, 4 achieving partial response, and 1 showing mixed response. Nine patients (45%) received local radiotherapy. At a median follow-up of 47 months (range, 17–91 months), none of these patients experienced relapse, progression, or secondary malignancy, or died. Three years after chemotherapy completion, none of the patients had experienced grade ≥3 late adverse effects.

Conclusion

Patients younger than 18 months with stage 4 MYCN nonamplified neuroblastoma showed excellent outcomes, without significant late adverse effects, when treated with alternating cycles of CEDC and ICE, followed by surgery and differentiation therapy.

Glutathione-mediated antioxidant response and aerobic metabolism: two crucial factors involved in determining the multi-drug resistance of high-risk neuroblastoma

Neuroblastoma, a paediatric malignant tumor, is initially sensitive to etoposide, a drug to which many patients develop chemoresistance. In order to investigate the molecular mechanisms responsible for etoposide chemoresistance, HTLA-230, a human MYCN-amplified neuroblastoma cell line, was chronically treated with etoposide at a concentration that in vitro mimics the clinically-used dose. The selected cells (HTLA-Chr) acquire multi-drug resistance (MDR), becoming less sensitive than parental cells to high doses of etoposide or doxorubicin. MDR is due to several mechanisms that together contribute to maintaining non-toxic levels of H₂O₂. In fact, HTLA-Chr cells, while having an efficient aerobic metabolism, are also characterized by an up-regulation of catalase activity and higher levels of reduced glutathione (GSH), a thiol antioxidant compound. The combination of such mechanisms contributes to prevent membrane lipoperoxidation and cell death. Treatment of HTLA-Chr cells with L-Buthionine-sulfoximine, an inhibitor of GSH biosynthesis, markedly reduces their tumorigenic potential that is instead enhanced by the exposure to N-Acetylcysteine, able to promote GSH synthesis.

Collectively, these results demonstrate that GSH and GSH-related responses play a crucial role in the acquisition of MDR and suggest that GSH level monitoring is an efficient strategy to early identify the onset of drug resistance and to control the patient's response to therapy.

MiRNA Influences in Neuroblast Modulation: An Introspective Analysis

Neuroblastoma (NB) is the most common occurring solid paediatric cancer in children under the age of five years. Whether of familial or sporadic origin, chromosome abnormalities contribute to the development of NB and cause dysregulation of microRNAs (miRNAs). MiRNAs are small non-coding, single stranded RNAs that target messenger RNAs at the post-transcriptional levels by repressing translation within all facets of human physiology. Such gene 'silencing' activities by miRNAs allows the development of regulatory feedback loops affecting multiple functions within the cell, including the possible differentiation of neural stem cell (NSC) lineage selection. Neurogenesis includes stages of self-renewal and fate specification of NSCs, migration and maturation of young neurones, and functional integration of new neurones into the neural circuitry, all of which are regulated by miRNAs. The role of miRNAs and their interaction in cellular processes are recognised aspects of cancer genetics, and miRNAs are currently employed as biomarkers for prognosis and tumour characterisation in multiple cancer models. Consequently, thorough understanding of the mechanisms of how these miRNAs interplay at the transcriptomic level will definitely lead to the development of novel, bespoke and efficient therapeutic measures, with this review focusing on the influences of miRNAs on neuroblast modulations leading to neuroblastoma.

Historical time to disease progression and progression-free survival in patients with recurrent/refractory neuroblastoma treated in the modern era on Children's Oncology Group early-phase trials

BACKGROUND

Early-phase trials in patients with recurrent neuroblastoma historically used an objective "response" of measureable disease (Response Evaluation Criteria In Solid Tumors [RECIST], without bone/bone marrow assessment) to select agents for further study. Historical cohorts may be small and potentially biased; to the authors' knowledge, disease recurrence studies from international registries are outdated. Using a large recent cohort of patients with recurrent/refractory neuroblastoma from Children's Oncology Group (COG) modern-era early-phase trials, the authors determined outcome and quantified parameters for designing future studies.

METHODS

The first early-phase COG trial enrollment (sequential) of 383 distinct patients with recurrent/refractory neuroblastoma on 23 phase 1, 3 phase 1/2, and 9 phase 2 trials (August 2002 to January 2014) was analyzed for progression-free survival (PFS), overall survival (OS), and time to disease progression (TTP). Planned frontline therapy for patients with high-risk neuroblastoma included hematopoietic stem cell transplantation (approximately two-thirds of patients underwent ≥1 hematopoietic stem cell transplantation); 13.2% of patients received dinutuximab.

RESULTS

From the time of the patient's first early-phase trial enrollment (383 patients), the 1-year and 4-year PFS rates ( ± standard error) were 21% ± 2% and 6% ± 1%, respectively, whereas the 1-year and 4-year OS rates were 57% ± 3% and 20% ± 2%, respectively. The median TTP was 58 days (interquartile range, 31-183 days [350 patients]); the median follow-up was 25.3 months (33 patients were found to be without disease recurrence/progression). The median time from diagnosis to first disease recurrence/progression was 18.7 months (range, 1.4-64.8 months) (176 patients). MYCN amplification and 11q loss of heterozygosity were prognostic of worse PFS and OS (P = .003 and P<.0001, respectively, and P = .02 and P = .03, respectively) after early-phase trial enrollment.

CONCLUSIONS

This recent COG cohort of patients with recurrent/refractory neuroblastoma is inclusive and representative. To the authors' knowledge, the current study is the first meta-analysis of PFS, TTP, and OS within the context of modern therapy. These results will inform the design of future phase 2 studies by providing a) historical context during the search for more effective agents; and, b) factors prognostic of PFS and OS after disease recurrence to stratify randomization. Cancer 2017;123:4914-23. © 2017 American Cancer Society.

MYCN-amplified stage 2/3 neuroblastoma: excellent survival in the era of anti-GD2 immunotherapy

High-risk neuroblastoma (HR-NB) includes MYCN-amplified stage 2/3, but reports covering anti-G_D2 immunotherapy, which recently became standard for HR-NB, do not provide details on this subset. We now report on all 20 MYCN-amplified stage 2/3 patients who received induction chemotherapy at our center during the era of consolidation with anti-G_D2 antibody 3F8/ granulocyte-macrophage colony-stimulating factor (GM-CSF) (2000-2015). Early in this period, consolidation included autologous stem-cell transplantation (ASCT). Event-free survival (EFS) and overall survival (OS) were estimated using Kaplan-Meier analyses. With induction, 19/20 (95%) patients achieved complete/very good partial remission (CR/VGPR) but one had progressive disease with early death. One responder did not receive consolidation and died of relapse. Five-year post-diagnosis EFS/OS rates for all 20 patients were 72%/84%. The 18 CR/VGPR patients who received consolidation had EFS/OS 81%/94% at five years from starting 3F8/GM-CSF: 4/4 ASCT patients remained relapse-free, while 11/14 non-ASCT patients remained relapse-free and two of the three relapsed patients achieved 2^nd CR (consolidated by retreatment with 3F8/GM-CSF) and remained in 2^nd CR at 36+ and 95+ months post-relapse. The 14 non-ASCT patients had EFS/OS 73.5%/93% at five years from starting 3F8/GM-CSF. This subset appears to have a good prognosis with contemporary multi-modality therapy, possibly even without ASCT.

Results of neuroblastoma treatment in Lithuania: a single centre experience

Background.

Neuroblastoma (NB) is the most common extracranial solid tumour in children. This is a very rare disease with heterogeneous biology varying from complete spontaneous regression to a highly aggressive tumour responsible for 15% of malignancy-related death in early childhood. Analyses of survival rates in Europe have shown a considerable difference between Northern/Western and Eastern European countries. Treatment results of NB in Lithuania have never been analyzed.

Aim.

To assess the survival rate of children with NB according to initial spread of the disease, age at diagnosis, the MYCN amplification, risk group, and treatment period.

Patients and methods.

A retrospective single-centre analysis of patients’ records was performed. Children diagnosed and treated for NB between 2000 and 2015 at the Centre of Paediatric Oncology and Haematology of the Children’s Hospital, Affiliate of Vilnius University Hospital Santaros Klinikos were included. The patients were divided into three groups according to the spread of the disease: group 1 – patients with local NB older than 12 years of age; group 2 – stage IV patients, also called the M stage; group 3 – infants with stages 4S and MS. The patients were stratified into three risk groups – low, intermediate and high risk. Estimates of five-year overall survival (OS_5y) were calculated using the Kaplan-Meier method comparing survival probability according to spread of the disease, age at diagnosis, the MYCN amplification, risk group and treatment period (2000–2007 vs 2008–2015).

Results.

Overall 60 children (31 girls and 29 boys) with NB were included. The median age at diagnosis was 1.87 years (ranged from 4 days to 15 years). Seventy-eight percent of cases were found to be differentiated or undifferentiated NB, 22% – ganglioneuroblastoma. The local form of the disease was predominant: 57% (34/60) of patients were allocated to the group 1, 37% (22/60) with initial metastatic disease were assigned to group 2, and infants with 4S or MS stage comprising 7% (4/60) allocated to group 3, respectively. The probability of OS_5y for the entire cohort was 71% with the median follow-up of 8.8 ± 4.8 years. The probability of OS_5y for local disease (group 1) was significantly higher compared to metastatic disease (group 2) (94% vs. 34%, p = 0.001, respectively) as well as for infants compared to children older than 12 months at the time of diagnosis (90% vs 60%, p = 0.009, respectively). The MYCN gene amplification had a negative influence on OS_5y, with 78% of MYCN-negative patients surviving in comparison to 40% of MYCN-positive patients who did not survive (p = 0.153). The high-risk patients had significantly worse OS_5y than children with intermediated or low risk (35% vs. 82% vs. 100%, respectively, p = 0.001). Comparison of OS_5y between two treatment periods in the entire patient population revealed a non-significant increase in survival from 66% in the 2000–2007 period to 82% in the 2008–2015 period (p = 0.291), mostly due to a dramatic improvement achieved for high-risk patients whose survival rate increased from 9% in the 2000–2007 period to 70% in the 2008–2015 period (p = 0.009).

Conclusions.

There was a slight predominance of low-risk patients, probably due to a higher number of infants. A better probability of OS_5y was confirmed in infants with local disease and in MYCN-negative patients. The OS_5y for children treated for NB at our institution over 16 years increased from 66% in the 2000–2007 period to 82% in the 2008–2015 period with the most significant improvement achieved for high risk patients. The current survival rate of children treated for NB at our institution is in line with the reported numbers in Northern and Western European countries.

Factors associated with recurrence and survival length following relapse in patients with neuroblastoma

Background:

Despite therapeutic advances, survival following relapse for neuroblastoma patients remains poor. We investigated clinical and biological factors associated with length of progression-free and overall survival following relapse in UK neuroblastoma patients.

Methods:

All cases of relapsed neuroblastoma, diagnosed during 1990–2010, were identified from four Paediatric Oncology principal treatment centres. Kaplan–Meier and Cox regression analyses were used to calculate post-relapse overall survival (PROS), post-relapse progression-free survival (PRPFS) between relapse and further progression, and to investigate influencing factors.

Results:

One hundred eighty-nine cases were identified from case notes, 159 (84.0%) high risk and 17 (9.0%), unresectable, MYCN non-amplified (non-MNA) intermediate risk (IR). For high-risk patients diagnosed >2000, median PROS was 8.4 months (interquartile range (IQR)=3.0–17.4) and median PRPFS was 4.7 months (IQR=2.1–7.1). For IR, unresectable non-MNA patients, median PROS was 11.8 months (IQR 9.0–51.6) and 5-year PROS was 24% (95% CI 7–45%). MYCN amplified (MNA) disease and bone marrow metastases at diagnosis were independently associated with worse PROS for high-risk cases. Eighty percent of high-risk relapses occurred within 2 years of diagnosis compared with 50% of unresectable non-MNA IR disease.

Conclusions:

Patients with relapsed HR neuroblastomas should be treatment stratified according to MYCN status and PRPFS should be the primary endpoint in early phase clinical trials. The failure to salvage the majority of IR neuroblastoma is concerning, supporting investigation of intensification of upfront treatment regimens in this group to determine whether their use would diminish likelihood of relapse.

Advances in the translational genomics of neuroblastoma: From improving risk stratification and revealing novel biology to identifying actionable genomic alterations

Neuroblastoma is an embryonal malignancy that commonly affects young children and is remarkably heterogenous in its malignant potential. Recently, the genetic basis of neuroblastoma has come into focus and not only has catalyzed a more comprehensive understanding of neuroblastoma tumorigenesis but also has revealed novel oncogenic vulnerabilities that are being therapeutically leveraged. Neuroblastoma is a model pediatric solid tumor in its use of recurrent genomic alterations, such as high-level MYCN (v-myc avian myelocytomatosis viral oncogene neuroblastoma-derived homolog) amplification, for risk stratification. Given the relative paucity of recurrent, activating, somatic point mutations or gene fusions in primary neuroblastoma tumors studied at initial diagnosis, innovative treatment approaches beyond small molecules targeting mutated or dysregulated kinases will be required moving forward to achieve noticeable improvements in overall patient survival. However, the clonally acquired, oncogenic aberrations in relapsed neuroblastomas are currently being defined and may offer an opportunity to improve patient outcomes with molecularly targeted therapy directed toward aberrantly regulated pathways in relapsed disease. This review summarizes the current state of knowledge about neuroblastoma genetics and genomics, highlighting the improved prognostication and potential therapeutic opportunities that have arisen from recent advances in understanding germline predisposition, recurrent segmental chromosomal alterations, somatic point mutations and translocations, and clonal evolution in relapsed neuroblastoma.

SIOP-PODC adapted risk stratification and treatment guidelines: Recommendations for neuroblastoma in low- and middle-income settings

Neuroblastoma is the most common extracranial solid tumor in childhood in high-income countries (HIC), where consistent treatment approaches based on clinical and tumor biological risk stratification have steadily improved outcomes. However, in low- and middle- income countries (LMIC), suboptimal diagnosis, risk stratification, and treatment may occur due to limited resources and unavailable infrastructure. The clinical practice guidelines outlined in this manuscript are based on current published evidence and expert opinions. Standard risk stratification and treatment explicitly adapted to graduated resource settings can improve outcomes for children with neuroblastoma by reducing preventable toxic death and relapse.

Clinico-epidemiology of neuroblastoma in north east Egypt: A 5-year multicenter study

Neuroblastoma, an embryonal malignancy of the sympathetic nervous system, is the most frequent extracranial solid tumor The clinico-epidemiological features of neuroblastoma in infants and children were investigated between January 2005 and January 2010 at the Pediatric Oncology units of Mansoura, Zagazig, and Tanta University Children's Hospitals (Egypt). Of 142 cases of neuroblastoma, 10 were omitted from the study due to defective data. The median age of the patients was 30 months, with 75.8% aged ≥1 year and 24.2% aged <1 year at time of diagnosis. The male-to-female ratio was 1.06. Suprarenal glands were the most common primary tumor site (72.7%). The majority of the patients (76.7%) had stage IV disease. Favorable pathology was observed in 43.8% of patients, while 56.2% exhibited unfavorable pathology. The estimated survival rate of patients was 30.7±10.0%, and mean survival time was 24.2±5.2 months. The rate of mortality was 28.6% for patients aged <1 year, and 81.8% for those aged ≥1 year (P=0.005). For patients with favorable pathology, the rate of mortality was significantly lower (28.6%) compared with that of patients with unfavorable pathology (77.8%; P=0.049). Although the association between outcome and each of the primary tumor sites, children's oncology group risk and gender was statistically insignificant, a large effect size was identified between outcome and primary tumor site, as well as children's oncology group risk and a medium effect size was identified between outcome and gender. Additionally, an age of ≥1 year was associated with unfavorable pathology (P=0.024), stage IV disease (P=0.026) and a suprarenal primary tumor site (P=0.001).

Early targets of miR-34a in neuroblastoma

Several genes encoding for proteins involved in proliferation, invasion, and apoptosis are known to be direct miR-34a targets. Here, we used proteomics to screen for targets of miR-34a in neuroblastoma (NBL), a childhood cancer that originates from precursor cells of the sympathetic nervous system. We examined the effect of miR-34a overexpression using a tetracycline inducible system in two NBL cell lines (SHEP and SH-SY5Y) at early time points of expression (6, 12, and 24 h). Proteome analysis using post-metabolic labeling led to the identification of 2,082 proteins, and among these 186 were regulated (112 proteins down-regulated and 74 up-regulated). Prediction of miR-34a targets via bioinformatics showed that 32 transcripts held miR-34a seed sequences in their 3'-UTR. By combining the proteomics data with Kaplan Meier gene-expression studies, we identified seven new gene products (ALG13, TIMM13, TGM2, ABCF2, CTCF, Ki67, and LYAR) that were correlated with worse clinical outcomes. These were further validated in vitro by 3'-UTR seed sequence regulation. In addition, Michigan Molecular Interactions searches indicated that together these proteins affect signaling pathways that regulate cell cycle and proliferation, focal adhesions, and other cellular properties that overall enhance tumor progression (including signaling pathways such as TGF-β, WNT, MAPK, and FAK). In conclusion, proteome analysis has here identified early targets of miR-34a with relevance to NBL tumorigenesis. Along with the results of previous studies, our data strongly suggest miR-34a as a useful tool for improving the chance of therapeutic success with NBL.

Treatment of two cases with refractory, metastatic intermediate-risk neuroblastoma with isotretenoin alone or observation

Patients <12 months with favorable biology, metastatic neuroblastoma have >90% overall survival following treatment with chemotherapy and surgery. We report two infants with favorable biology, stage 4 neuroblastoma with refractory disease after standard intermediate-risk chemotherapy and additional retrieval chemotherapy. One patient was treated with six additional cycles of isotretinoin and the other observed. Both remain clinically well with persistent disease but no evidence of tumor progression for 28 and 13 months following completion of cytotoxic treatment. Similar to residual tumor in primary sites, refractory metastatic disease may not portend a poor outcome in patients with favorable biology, intermediate-risk neuroblastoma.

Therapeutic targets for neuroblastomas

INTRODUCTION

Neuroblastoma (NB) is the most common and deadly solid tumor in children. Despite recent improvements, the long-term outlook for high-risk NB is still < 50%. Further, there is considerable short- and long-term toxicity. More effective, less toxic therapy is needed, and the development of targeted therapies offers great promise.

AREAS COVERED

Relevant literature was reviewed to identify current and future therapeutic targets that are critical to malignant transformation and progression of NB. The potential or actual NB therapeutic targets are classified into four categories: i) genes activated by amplification, mutation, translocation or autocrine overexpression; ii) genes inactivated by deletion, mutation or epigenetic silencing; iii) membrane-associated genes expressed on most NBs but few other tissues; or iv) common target genes relevant to NB as well as other tumors.

EXPERT OPINION

Therapeutic approaches have been developed to some of these targets, but many remain untargeted at the present time. It is unlikely that single targeted agents will be sufficient for long-term cure, at least for high-risk NBs. The challenge will be how to integrate targeted agents with each other and with conventional therapy to enhance their efficacy, while simultaneously reducing systemic toxicity.

Presence of differentiating neuroblasts in bone marrow is a favorable prognostic factor for bone marrow metastatic neuroblastoma at diagnosis

Background

The prognostic impact of the presence of differentiating neuroblasts in bone marrow (BM) remains unclear in BM metastatic neuroblastoma (NB). We aimed to identify the prognostic impact of differentiating neuroblasts in BM at diagnosis and after chemotherapy.

Methods

A total of 51 patients diagnosed with BM metastatic NB at Asan Medical Center between January 1990 and July 2005 were enrolled. BM histology and laboratory data along with overall survival (OS) were compared with regard to the differentiation status of neuroblasts in BM at diagnosis and after chemotherapy.

Results

Among the 51 patients, 13 (25.5%) exhibited differentiating neuroblasts in BM at diagnosis and 17/51 (33.3%) exhibited them after chemotherapy. The only significant difference among patient groups was the improved OS in patients with differentiated neuroblasts in BM at diagnosis (P=0.021). In contrast, the differentiation status of neuroblasts in BM after chemotherapy did not affect OS (P=0.852).

Conclusions

Our study is the first report describing the presence of differentiating neuroblasts in BM. The presence of differentiating neuroblasts in BM at diagnosis may be a favorable prognostic factor for patients with BM metastatic NB; however, the same phenomenon after chemotherapy is irrelevant to prognosis.

MYCN-mediated overexpression of mitotic spindle regulatory genes and loss of p53-p21 function jointly support the survival of tetraploid neuroblastoma cells

High-risk neuroblastomas often harbor structural chromosomal alterations, including amplified MYCN, and usually have a near-di/tetraploid DNA index, but the mechanisms creating tetraploidy remain unclear. Gene-expression analyses revealed that certain MYCN/MYC and p53/pRB-E2F target genes, especially regulating mitotic processes, are strongly expressed in near-di/tetraploid neuroblastomas. Using a functional RNAi screening approach and live-cell imaging, we identified a group of genes, including MAD2L1, which after knockdown induced mitotic-linked cell death in MYCN-amplified and TP53-mutated neuroblastoma cells. We found that MYCN/MYC-mediated overactivation of the metaphase-anaphase checkpoint synergizes with loss of p53-p21 function to prevent arrest or apoptosis of tetraploid neuroblastoma cells.

Utilisation of nanoparticle technology in cancer chemoresistance

The implementation of cytotoxic chemotherapeutic drugs in the fight against cancer has played an invariably essential role for minimizing the extent of tumour progression and/or metastases in the patient and thus allowing for longer event free survival periods following chemotherapy. However, such therapeutics are nonspecific and bring with them dose-dependent cumulative adverse effects which can severely exacerbate patient suffering. In addition, the emergence of innate and/or acquired chemoresistance to the exposed cytotoxic agents undoubtedly serves to thwart effective clinical efficacy of chemotherapy in the cancer patient. The advent of nanotechnology has led to the development of a myriad of nanoparticle-based strategies with the specific goal to overcome such therapeutic hurdles in multiple cancer conditions. This paper aims to provide a brief overview and recollection of all the latest advances in the last few years concerning the application of nanoparticle technology to enhance the safe and effective delivery of chemotherapeutic agents to the tumour site, together with providing possible solutions to circumvent cancer chemoresistance in the clinical setting.

Clinical significance of tumor-associated inflammatory cells in metastatic neuroblastoma

PURPOSE

Children diagnosed at age ≥ 18 months with metastatic MYCN-nonamplified neuroblastoma (NBL-NA) are at high risk for disease relapse, whereas those diagnosed at age < 18 months are nearly always cured. In this study, we investigated the hypothesis that expression of genes related to tumor-associated inflammatory cells correlates with the observed differences in survival by age at diagnosis and contributes to a prognostic signature.

METHODS

Tumor-associated macrophages (TAMs) in localized and metastatic neuroblastomas (n = 71) were assessed by immunohistochemistry. Expression of 44 genes representing tumor and inflammatory cells was quantified in 133 metastatic NBL-NAs to assess age-dependent expression and to develop a logistic regression model to provide low- and high-risk scores for predicting progression-free survival (PFS). Tumors from high-risk patients enrolled onto two additional studies (n = 91) served as independent validation cohorts.

RESULTS

Metastatic neuroblastomas had higher infiltration of TAMs than locoregional tumors, and metastatic tumors diagnosed in patients at age ≥ 18 months had higher expression of inflammation-related genes than those in patients diagnosed at age < 18 months. Expression of genes representing TAMs (CD33/CD16/IL6R/IL10/FCGR3) contributed to 25% of the accuracy of a novel 14-gene tumor classification score. PFS at 5 years for children diagnosed at age ≥ 18 months with NBL-NA with a low- versus high-risk score was 47% versus 12%, 57% versus 8%, and 50% versus 20% in three independent clinical trials, respectively.

CONCLUSION

These data suggest that interactions between tumor and inflammatory cells may contribute to the clinical metastatic neuroblastoma phenotype, improve prognostication, and reveal novel therapeutic targets.

The significance of serial histopathology in a residual mass for outcome of intermediate risk stage 3 neuroblastoma

BACKGROUND

To describe the serial histopathology of intermediate risk stage 3 neuroblastoma after chemotherapy, and correlate with residual mass at therapy completion and outcome.

PROCEDURE

A retrospective review of intermediate risk stage 3 neuroblastoma patients treated 1989-2005 at Children's Hospital Los Angeles according to CCG 3881 or CCG 3961 protocols was performed, with central review of histopathology, radiology, and surgery.

RESULTS

Eighteen patients treated per CCG 3881 (n = 9) or CCG 3961 (n = 9), with including 1 (n = 5), 2 (n = 9), ≥ 3 (n = 3), or unknown number (n = 1) of surgical procedures were included. At therapy completion, 10 patients had residual tumor: <10% original size (n = 3), >10% original size (n = 6) (5 MIBG avid; 4 with elevated catecholamines), and CT non-measurable MIBG avid tumor (n = 1). Post-chemotherapy histology showed tumor regression (n = 4); or maturation with (n = 6) or without (n = 2) Schwannian development. Histologic changes correlated with median tumor shrinkage of 80% (regressing tumors) and <25% (maturing tumors). Tumor size increased in one patient with maturing tumor and Schwannian development. Overall survival was 100%.

CONCLUSION

Post-chemotherapy histopathology of intermediate risk stage 3 neuroblastoma was characterized by regression or maturation. Persisting residual and maturing tumors were not associated with tumor progression, despite MIBG uptake and/or elevated catecholamines, supporting observation only. Histopathology should be obtained in future studies to confirm these findings, and guide length of chemotherapy.

Enhanced anti-neuroblastoma activity of a fenretinide complexed form after intravenous administration

OBJECTIVES

The major limitation to successful chemotherapy of neuroblastoma (NB) is the toxicity and the poor bioavailability of traditional drugs.

METHODS

We synthesised an amphiphilic dextrin derivative (DX-OL) able to host fenretinide (4-HPR) by complexation. In this study, we have investigated the effects of 4-HPR-loaded amphipilic dextrin (DX-OL/4-HPR) in comparison with 4-HPR alone both in vitro on human NB cells and in vivo in pseudometastatic NB models. The haemolysis assay was used as a measure of the potential damage caused by the pharmaceutical formulation in vivo. Pharmacokinetic experiments were performed to assess drug plasma levels in mice treated with free or complexed 4-HPR.

KEY FINDINGS

DX-OL/4-HPR exerted a more potent cytotoxic activity on NB cells. Complexed 4-HPR significantly increased the proportion of sub-G1 cells with respect to free 4-HPR. Dextrin derivatives showed no haemolytic activity, indicating their suitability for parenteral administration. DX-OL/4-HPR increased the lifespan and the long-term survival of treated mice over controls. The analysis of drug plasma levels indicates that the complexed drug has a higher AUC due to a reduced clearance from the blood.

CONCLUSIONS

Our data suggest that DX-OL/4-HPR is an injectable formulation that is able to improve drug aqueous solubility and bioavailability.

The antioxidant status and response to therapy in children with soft tissue sarcomas and neuroblastoma

BACKGROUND

Antioxidant systems in cells maintain the proper homeostasis of reactive oxygen species, which at high concentrations can induce carcinogenesis. The aim of this study was to evaluate the serum levels of ischemia-modified albumin (IMA), erythrocyte superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) as markers for prognosis in children with neuroblastoma (NB) and soft tissue sarcomas (STS), two cancer types for which reliable prognostic factors are needed.

PROCEDURE

SOD, GSH-Px, and IMA were measured before and during responses to therapy assessment in 99 children with NB and STS and in 30 healthy controls.

RESULTS

There were no statistically significant differences in the erythrocyte SOD and GSH-Px activities between the patients with cancer and healthy controls. The levels of IMA in patients with STS and NB were found to be significantly higher than in the controls (P = 0.0013; P = 0.0066, and 0.0164, respectively). Decreased activities of SOD and GSH-Px were found in all patients with poor-responding (PRS) cancers and decreased SOD activity was found in patients with PRS NB. An increase in GSH-Px was observed in patients with good-responding (GR) NB. All patients with GR cancers demonstrated higher SOD and GSH-Px activities than patients with PRS cancers.

CONCLUSIONS

While determining the levels of specific antioxidants as antioxidant-barrier parameters in children with cancer may be valuable in predicting therapeutic responses as well as outcomes, additional studies are required.

Differential toll-like receptor 3 (TLR3) expression and apoptotic response to TLR3 agonist in human neuroblastoma cells

Background

Toll-like receptor-3 (TLR-3) is a critical component of innate immune system against dsRNA viruses and is expressed in the central nervous system. However, it remains unknown whether TLR3 may serve as a therapeutic target in human neuroblastoma (NB).

Methods

TLR3 expression in human NB samples was examined by immunohistochemical analysis. Quantitative RT-PCR and western blot was used to determine TLR3 expression in three human NB cell lines. The effect of TLR3 agonist, polyinosinic-polycytidylic acid (poly(I:C)), on the growth of human NB cells was evaluated by WST-1 cell proliferation assay, flow cytometry analysis, and immunoblot analysis. Blockade of TLR3 signaling was achieved using TLR3 neutralizing antibody, small interference RNA, and 2-aminopurine (2-AP), an inhibitor of protein kinase R (PKR), an interferon-induced, double-stranded RNA-activated protein kinase.

Results

In immunohistochemical studies, TLR3 mainly expressed in the cytoplasm of ganglion cells and in some neuroblastic cells, but not in the stromal cells in human NB tissues. Among three human NB cell lines analyzed, TLR3 was significantly up-regulated in SK-N-AS cells at mRNA and protein level compared with other two low TLR3- expressing NB cells. Treatment with poly(I:C) elicited significant growth inhibition and apoptosis only in high TLR3-expressing SK-N-AS cells, but not in low TLR3-expressing SK-N-FI and SK-N-DZ cells. Moreover, poly(I:C) treatment significantly stimulated the activities of PKR, interferon regulatory factor 3 (IRF-3) and caspase-3 in SK-N-AS cells. Application of TLR3 neutralizing antibody or small interference RNA (siRNA) reduced the poly(I:C)-induced inhibition of cell proliferation and apoptosis in SK-N-AS cells. On the contrary, ectopic TLR3 expression enhanced the sensitivity of low TLR3-expressing NB cells to poly(I:C). Finally, application of 2-AP attenuated the poly(I:C)-induced IRF-3 and caspase-3 activation in SK-N-AS cells.

Conclusion

The present study demonstrates that TLR3 is expressed in a subset of NB cells. Besides, TLR3/PKR/IRF-3/capase-3 pathway is implicated in the selective cytotoxicity of TLR3 agonist towards high TLR3-expressing NB cells.

Bcl6 is expressed in neuroblastoma: tumor cell type-specific expression predicts outcome

Neuroblastoma (NB) is the most common extracranial solid neoplasm of infancy and childhood. Whereas most low-risk patients do well, children with high-risk tumors often fail intensive treatment. Identification of novel biomarkers is critical to improve prognostication, tailor therapy, and develop new therapeutic targets. Differential RNA-level expression between tumor cells with neuroblastic (N-type) and Schwannian stromal (S-type) phenotypes was used to identify genes of potential interest based on tumor cell type-specific regulation. Gene expression microarray analysis revealed marked differences between N-type and S-type cells in their levels of BCL6 messenger RNA, a transcriptional regulator overexpressed in a variety of hematopoietic malignancies. S-type cells express higher levels of Bcl6 RNA and protein than N-type, and protein levels are significantly limited by proteasome function. An NB tumor tissue microarray linked to clinicopathologic data was immunohistochemically stained to measure Bcl6 protein levels. Bcl6 was detected in both the neuroblastic and Schwannian stromal regions, as distinguished histologically, and correlated with outcome. We found that expression in neuroblastic regions differentiates outcomes, in that Bcl6 expression in neuroblastic regions is associated with increased time to relapse and increased overall survival compared with absent expression in neuroblastic regions, regardless of Schwannian stromal expression. Thus, our findings suggest that Bcl6 may be useful as a prognostic marker and might represent a potential therapeutic target for high-risk NB.

Disparities in cancer outcomes: lessons learned from children with cancer

Disparities in cancer burden by race/ethnicity have been reported, primarily in adults with cancer. However, there appear to be gaps in the pediatric oncology literature with regards to a comprehensive overview on this topic. Extant literature is used to highlight the results of studies focusing on racial and ethnic disparities in outcome observed in selected childhood cancers. A comprehensive approach is utilized to understand possible underlying causes of disparities in cancer outcomes, and to highlight the gaps that currently exist. This review helps define areas of future research that could help develop targeted, disease-specific approaches to eliminate the disparities.

Seeking consent to tissue banking: a survey of health professionals in childhood cancer

To identify the views of health professionals working in childhood cancer on seeking consent to tissue banking from potential donors. Self-completion questionnaires sent to 553 UK paediatric oncology health professionals. The response rate was 60%. Respondents (100%) were in favour of using tissue samples from children with cancer for research. A substantial minority (30%) had concerns about the impact of the law on their professional role in relation to tissue banking. Almost all (90%) reported that both the parent(s) and the child, if able, should be asked for consent, though the UK Human Tissue Act provides that a competent child's consent is sufficient. Most (94%) supported 'generic' rather than 'specific' consent. Barriers to obtaining consent included: (1) timing of the approach to families; (2) availability of suitable staff; (3) sensitivity of the issues; (4) difficulties of managing the process; and (5) problems of maintaining a paper trail. Many would welcome training on seeking consent. Personal knowledge and relationships with families are often seen as important in guiding the proper approach to consent rather than formalized rules. There is widespread support among health professionals for tissue banking in childhood cancer. In sensitive situations, disciplined exercise of professional discretion might better deliver on aspirations for regulation than rigid procedures.

Treatment results and prognostic factors of pediatric neuroblastoma: a retrospective study

BACKGROUND

We conducted a retrospective analysis to investigate treatment results and prognostic factors of pediatric neuroblastoma patients.

METHODS

This retrospective study was carried out analyzing the medical records of patients with the pathological diagnosis of neuroblastoma seen at South Egypt Cancer Institute, Assiut University during the period from January 2001 and January 2010. After induction chemotherapy, response according to international neuoblastoma response criteria was assessed. Radiotherapy to patients with residual primary tumor was applied. Overall and event free survival (OAS and EFS) rates were estimated using Graphed prism program. The Log-rank test was used to examine differences in OAS and EFS rates. Cox-regression multivariate analysis was done to determine the independent prognostic factors affecting survival rates.

RESULTS

Fifty three cases were analyzed. The median follow-up duration was 32 months and ranged from 2 to 84 months. The 3-year OAS and EFS rates were 39.4% and 29.3% respectively. Poor prognostic factors included age >1 year of age, N-MYC amplification, and high risk group. The majority of patients (68%) presented in high risk group, where treatment outcome was poor, as only 21% of patients survived for 3 year.

CONCLUSION

Multivariate analysis confirmed only the association between survival and risk group. However, in univariate analysis, local radiation therapy resulted in significant survival improvement. Therefore, radiotherapy should be given to patients with residual tumor evident after induction chemotherapy and surgery. Future attempts to improve OAS in high risk group patients with aggressive chemotherapy and bone marrow transplantation should be considered.

Racial and ethnic disparities in risk and survival in children with neuroblastoma: a Children's Oncology Group study

PURPOSE

Although health disparities are well-described for many cancers, little is known about racial and ethnic disparities in neuroblastoma. To evaluate differences in disease presentation and survival by race and ethnicity, data from the Children's Oncology Group (COG) were analyzed.

PATIENTS AND METHODS

The racial/ethnic differences in clinical and biologic risk factors, and outcome of patients with neuroblastoma enrolled on COG ANBL00B1 between 2001 and 2009 were investigated.

RESULTS

A total of 3,539 patients (white, 72%; black, 12%; Hispanic, 12%; Asian, 4%; and Native American, < 1%) with neuroblastoma were included. The 5-year event-free survival (EFS) rates were 67% for whites (95% CI, 65% to 69%), 69% for Hispanics (95% CI, 63% to 74%), 62% for Asians (95% CI, 51% to 71%), 56% for blacks (95% CI, 50% to 62%), and 37% for Native American (95% CI, 17% to 58%). Blacks (P < .001) and Native Americans (P = .04) had a higher prevalence of high-risk disease than whites, and significantly worse EFS (P = .01 and P = .002, respectively). Adjustment for risk group abrogated these differences. However, closer examination of the EFS among high-risk patients who remained event free for 2 years or longer, revealed a higher prevalence of late-occurring events among blacks compared with whites (hazard ratio, 1.5; 95% CI, 1.0 to 2.3; P = .04).

CONCLUSION

Black and Native American patients with neuroblastoma have a higher prevalence of high-risk disease, accounting for their worse EFS when compared with whites. The higher prevalence of late-occurring events among blacks with high-risk disease suggests that this population may be more resistant to chemotherapy. Studies focused on delineating the genetic basis for the racial disparities observed in this study are planned.

Outcome after reduced chemotherapy for intermediate-risk neuroblastoma

BACKGROUND

The survival rate among patients with intermediate-risk neuroblastoma who receive dose-intensive chemotherapy is excellent, but the survival rate among patients who receive reduced doses of chemotherapy for shorter periods of time is not known.

METHODS

We conducted a prospective, phase 3, nonrandomized trial to determine whether a 3-year estimated overall survival of more than 90% could be maintained with reductions in the duration of therapy and drug doses, using a tumor biology-based therapy assignment. Eligible patients had newly diagnosed, intermediate-risk neuroblastoma without MYCN amplification; these patients included infants (<365 days of age) who had stage 3 or 4 disease, children (≥365 days of age) who had stage 3 tumors with favorable histopathological features, and infants who had stage 4S disease with a diploid DNA index or unfavorable histopathological features. Patients who had disease with favorable histopathological features and hyperdiploidy were assigned to four cycles of chemotherapy, and those with an incomplete response or either unfavorable feature were assigned to eight cycles.

RESULTS

Between 1997 and 2005, a total of 479 eligible patients were enrolled in this trial (270 patients with stage 3 disease, 178 with stage 4 disease, and 31 with stage 4S disease). A total of 323 patients had tumors with favorable biologic features, and 141 had tumors with unfavorable biologic features. Ploidy, but not histopathological features, was significantly predictive of the outcome. Severe adverse events without disease progression occurred in 10 patients (2.1%), including secondary leukemia (in 3 patients), death from infection (in 3 patients), and death at surgery (in 4 patients). The 3-year estimate (±SE) of overall survival for the entire group was 96±1%, with an overall survival rate of 98±1% among patients who had tumors with favorable biologic features and 93±2% among patients who had tumors with unfavorable biologic features.

CONCLUSIONS

A very high rate of survival among patients with intermediate-risk neuroblastoma was achieved with a biologically based treatment assignment involving a substantially reduced duration of chemotherapy and reduced doses of chemotherapeutic agents as compared with the regimens used in earlier trials. These data provide support for further reduction in chemotherapy with more refined risk stratification. (Funded by the National Cancer Institute; ClinicalTrials.gov number, NCT00003093.)

Systems biology and modeling in neuroblastoma: practicalities and perspectives

Neuroblastoma (NB) is a common pediatric malignancy characterized by clinical and biological heterogeneity. A host of prognostic markers are available, contributing to accurate risk stratification and appropriate treatment allocation. Unfortunately, outcome is still poor for many patients, indicating the need for a new approach with enhanced utilization of the available biological data. Systems biology is a holistic approach in which all components of a biological system carry equal importance. Systems biology uses mathematical modeling and simulation to investigate dynamic interactions between system components, as a means of explaining overall system behavior. Systems biology can benefit the biomedical sciences by providing a more complete understanding of human disease, enhancing the development of targeted therapeutics. Systems biology is largely contiguous with current approaches in NB, which already employ an integrative and pseudo-holistic approach to disease management. Systems modeling of NB offers an optimal method for continuing progression in this field, and conferring additional benefit to current risk stratification and management. Likewise, NB provides an opportunity for systems biology to prove its utility in the context of human disease, since the biology of NB is comprehensively characterized and, therefore, suited to modeling. The purpose of this review is to outline the benefits, challenges and fundamental workings of systems modeling in human disease, using a specific example of bottom-up modeling in NB. The intention is to demonstrate practical requirements to begin bridging the gap between biological research and applied mathematical approaches for the mutual gain of both fields, and with additional benefits for clinical management.

Accumulation of segmental alterations determines progression in neuroblastoma

PURPOSE

Neuroblastoma is characterized by two distinct types of genetic profiles, consisting of either numerical or segmental chromosome alterations. The latter are associated with a higher risk of relapse, even when occurring together with numerical alterations. We explored the role of segmental alterations in tumor progression and the possibility of evolution from indolent to aggressive genomic types.

PATIENTS AND METHODS

Array-based comparative genomic hybridization data of 394 neuroblastoma samples were analyzed and linked to clinical data.

RESULTS

Integration of ploidy and genomic data indicated that pseudotriploid tumors with mixed numerical and segmental profiles may be derived from pseudotriploid tumors with numerical alterations only. This was confirmed by the analysis of paired samples, at diagnosis and at relapse, as in tumors with a purely numerical profile at diagnosis additional segmental alterations at relapse were frequently observed. New segmental alterations at relapse were also seen in patients with segmental alterations at diagnosis. This was not linked to secondary effects of cytotoxic treatments since it occurred even in patients treated with surgery alone. A higher number of chromosome breakpoints were correlated with advanced age at diagnosis, advanced stage of disease, with a higher risk of relapse, and a poorer outcome.

CONCLUSION

These data provide further evidence of the role of segmental alterations, suggesting that tumor progression is linked to the accumulation of segmental alterations in neuroblastoma. This possibility of genomic evolution should be taken into account in treatment strategies of low- and intermediate-risk neuroblastoma and should warrant biologic reinvestigation at the time of relapse.

Improved survival of children with neuroblastoma between 1979 and 2005: a report of the Italian Neuroblastoma Registry

PURPOSE

To describe treatment, clinical course, and survival of a cohort of Italian patients with neuroblastoma.

PATIENTS AND METHODS

The study includes data from 2,216 children (age 0 to 14 years) diagnosed between 1979 and 2005. Overall survival (OS) was analyzed by clinical and biologic features at presentation and periods of diagnosis: 1979 to 1984, 1985 to 1991, 1992 to 1998, and 1999 to 2005. The relative risk of second malignant neoplasm (SMN) was assessed by the standardized incidence ratio (SIR), with the Italian population selected as referent.

RESULTS

Yearly patient accrual increased over time from 58 to 102. Patients age 0 to 17 months represented 45.6% of the total population, and their incidence increased over time from 36.5% to 48.5%. The incidence of stage 1 patients increased over time from 5.8% to 23.2%. A total of 898 patients (40.5%) developed disease progression or relapse, 19 patients developed SMN, and two patients developed myelodysplasia. The cumulative risk of SMN at 20 years was 7.1%, for an SIR of 8.4 (95% CI, 5.1 to 13.2). A total of 858 patients (39%) died (779 of disease, 71 of toxicity, six of SMN, and two of tumor-unrelated surgical complications). Ten-year OS was 55.3% (95% CI, 53.0% to 57.6%) and increased over time from 34.9% to 65.0%; it was significantly better for females and patients age 0 to 17 months at diagnosis, with extra-abdominal primary, and stage 1 and 2 disease. OS improved significantly over time in stage 1 and 3 patients. In patients with stage 4 disease, the improvement occurred between the first and second time cohorts (6.7% v 23.5%), but not afterward.

CONCLUSION

The outcome of children with neuroblastoma has progressively improved. Long-term survivors bear a significant risk of SMN.

Neuroblastoma: Therapeutic strategies for a clinical enigma

Neuroblastoma, the most common extracranial pediatric solid tumor remains a clinical enigma with outcomes ranging from cure in >90% of patients with locoregional tumors with little to no cytotoxic therapy, to <30% for those >18months of age at diagnosis with metastatic disease despite aggressive multimodality therapy. Age, stage and amplification of the MYCN oncogene are the most validated prognostic markers. Recent research has shed light on the biology of neuroblastoma allowing more accurate stratification of patients which has permitted reducing or withholding cytotoxic therapy without affecting outcome for low-risk patients. However, for children with high-risk disease, the development of newer therapeutic strategies is necessary. Current surgery and radiotherapy techniques in conjunction with induction chemotherapy have greatly reduced the risk of local relapse. However, refractory or recurrent osteomedullary disease occurs in most patients with high-risk neuroblastoma. Toxicity limits for high-dose chemotherapy appear to have been reached without further clinical benefit. Neuroblastoma is the first pediatric cancer for which monoclonal-antibody-based immunotherapy has been shown to be effective, particularly for metastatic osteomedullary disease. Radioimmunotherapy appears to be a critical component of a recent, successful regimen for treating patients who relapse in the central nervous system, a possible sanctuary site. Efforts are under way to refine and enhance antibody-based immunotherapy and to determine its optimal use. The identification of newer tumor targets and the harnessing of cell-mediated immunotherapy may generate novel therapeutic approaches. It is likely that a combination of therapeutic modalities will be required to improve survival and cure rates.

Autologous and allogeneic cellular therapies for high-risk pediatric solid tumors

Since the 1950s, the overall survival of children with cancer has gone from almost zero to approaching 80%. Although there have been notable successes in treating solid tumors such as Wilms tumor, some childhood solid tumors have continued to elude effective therapy. With the use of megatherapy techniques such as tandem transplantation, dose escalation has been pushed to the edge of dose-limiting toxicities, and any further improvements in event-free survival will have to be achieved through novel therapeutic approaches. This article reviews the status of autologous and allogeneic hematopoietic stem cell transplantation (HSCT) for many pediatric solid tumor types. Most of the clinical experience in transplant for pediatric solid tumors is in the autologous setting, so some general principles of autologous HSCT are reviewed. The article then examines HSCT for diseases such as Hodgkin disease, Ewing sarcoma, and neuroblastoma, and the future of cell-based therapies by considering some experimental approaches to cell therapies.