Disseminated neuroblastoma in children older than one year at diagnosis: comparable results with three consecutive high-dose protocols adopted by the Italian Co-Operative Group for Neuroblastoma

Survival Benefit of Myeloablative Therapy with Autologous Stem Cell Transplantation in High-Risk Neuroblastoma: A Systematic Literature Review

BACKGROUND

Multimodal treatment of newly diagnosed high-risk neuroblastoma (HRNB) includes induction chemotherapy, consolidation with myeloablative therapy (MAT) and autologous stem cell transplantation (ASCT), followed by anti-disialoganglioside 2 (GD2) immunotherapy, as recommended by the Children's Oncology Group (COG) and the Society of Paediatric Oncology European Neuroblastoma (SIOPEN). Some centres proposed an alternative approach with induction chemotherapy followed by anti-GD2 immunotherapy, without MAT+ASCT.

OBJECTIVE

The aim of this systematic literature review was to compare survival outcomes in patients with HRNB treated with or without MAT+ASCT and with or without subsequent anti-GD2 immunotherapy.

PATIENTS AND METHODS

The review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. MEDLINE via PubMed and EMBASE databases were systematically searched for randomised controlled trials (RCT) and observational comparative studies in patients with HRNB using search terms for 'neuroblastoma' and ('myeloablative therapy' OR 'stem cell transplantation'). Reporting of at least one survival outcome [event-free survival (EFS), progression-free survival, relapse-free survival and/or overall survival (OS)] was required for inclusion. Outcomes from RCTs were synthesized in meta-analysis, while meta-analysis of non-RCTs was not planned owing to expected heterogeneity.

RESULTS

Literature searches produced 2587 results with 41 publications reporting 34 comparative studies included in the review. Of these, 7 publications reported 4 RCTs, and 34 publications reported 30 non-RCT studies. Studies differed with respect to included populations, induction regimen, response to induction, additional treatments and transplantation procedures. Subsequent treatments of relapse were rarely reported and could not be compared. In the meta-analysis, EFS was in favour of MAT+ASCT over conventional chemotherapy or no further treatment [hazard ratio (HR) = 0.78, 95% confidence interval (CI) 0.67-0.91, p = 0.001] with a trend favouring MAT+ASCT for OS (HR = 0.86, 95% CI 0.73-1.00, p = 0.05). Tandem MAT+ASCT was found to improve EFS compared with the single procedure, with improvement in both EFS and OS in patients treated with anti-GD2 therapy. Non-RCT comparative studies were broadly consistent with evidence from the RCTs; however, not all reported survival benefits of MAT+ASCT (single or tandem). Limited comparative evidence on treatment without MAT+ASCT in patients treated with anti-GD2 immunotherapy suggests an increased risk of relapse. In relapsed patients, MAT+ASCT appears to improve OS, but evidence remains scarce.

CONCLUSIONS

Survival benefits in patients treated with MAT+ASCT confirm that the procedure should remain an integral part of multimodal therapy. In patients treated with anti-GD2 immunotherapy, limited evidence suggests that omitting MAT+ASCT is associated with an increased risk of relapse, and therefore, a change in clinical practice can currently not be recommended. Evidence suggests the use of tandem MAT+ASCT compared with the single procedure, with greater benefits observed in patients treated with anti-GD2 immunotherapy. Limited evidence also suggests improved survival following MAT+ASCT in relapsed patients, which needs to be viewed in light of emerging chemoimmunotherapy in this setting.

Computational intelligence analysis of high-risk neuroblastoma patient health records reveals time to maximum response as one of the most relevant factors for outcome prediction

OBJECTIVE

Seek new candidate prognostic markers for neuroblastoma outcome, relapse or progression.

MATERIALS AND METHODS

In this multicentre and retrospective study, Random Forests coupled with recursive feature elimination techniques were applied to electronic records (55 clinical features) of 3034 neuroblastoma patients. To assess model performance and feature importance, dataset was split into a training set (80%) and a test set (20%).

RESULTS

In the test set, the mean Matthews correlation coefficient for the Random Forests models was greater than 0.46. Feature importance analysis revealed that, together with maximum response to first-line treatment (D_MAX_RESP), time to maximum response to first-line treatment (TIME_MAX_RESP.days) is a relevant predictor of both patients' outcome and relapse\progression. We showed the prognostic value of the max response to first-line treatment in clinically relevant subsets of high-, intermediate-, and low-risk patients for both overall and relapse-free survival (Log-rank p-value<0.0001). In high-risk patients older than 18 months and stage 4 tumour achieving a complete response or very good partial response, patients who exhibited a D_MAX_RESP greater than 9 months showed a better prognosis with respect to patients achieving D_MAX_RESP earlier than 9 months (overall survival): hazard ratio 3.3 95% confidence interval 1.8-5.9, Log-rank p-value p < 0.0001; relapse-free survival: 3.2 95%CI 1.8-5.6, Log-rank p-value p < 0.0001).

CONCLUSION

Our findings evidence the emerging role of the TIME_MAX_RESP.days in addition to the D_MAX_RESP as relevant predictors of outcome and relapse\progression in neuroblastoma with potential clinical impact on the management and treatment of patients.

A novel cuproptosis-related subtypes and gene signature associates with immunophenotype and predicts prognosis accurately in neuroblastoma

Background

Neuroblastoma (NB) is the most frequent solid tumor in pediatrics, which accounts for roughly 15% of cancer-related mortality in children. NB exhibited genetic, morphologic, and clinical heterogeneity, which limited the efficacy of available therapeutic approaches. Recently, a new term 'cuproptosis' has been used to denote a unique biological process triggered by the action of copper. In this instance, selectively inducing copper death is likely to successfully overcome the limitations of conventional anticancer drugs. However, there is still a gap regarding the role of cuproptosis in cancer, especially in pediatric neuroblastoma.

Methods

We characterized the specific expression of cuproptosis-related genes (CRGs) in NB samples based on publicly available mRNA expression profile data. Consensus clustering and Lasso-Cox regression analysis were applied for CRGs in three independent cohorts. ESTIMATE and Xcell algorithm was utilized to visualize TME score and immune cell subpopulations' relative abundances. Tumor Immune Dysfunction and Exclusion (TIDE) score was used to predict tumor response to immune checkpoint inhibitors. To decipher the underlying mechanism, GSVA was applied to explore enriched pathways associated with cuproptosis signature and Connectivity map (CMap) analysis for drug exploration. Finally, qPCR verified the expression levels of risk-genes in NB cell lines. In addition, PDHA1 was screened and further validated by immunofluorescence in human clinical samples and loss-of-function assays.

Results

We initially classified NB patients according to CRGs and identified two cuproptosis-related subtypes that were associated with prognosis and immunophenotype. After this, a cuproptosis-related prognostic model was constructed and validated by LASSO regression in three independent cohorts. This model can accurately predict prognosis, immune infiltration, and immunotherapy responses. These genes also showed differential expression in various characteristic groups of all three datasets and NB cell lines. Loss-of-function experiments indicated that PDHA1 silencing significantly suppressed the proliferation, migration, and invasion, in turn, promoted cell cycle arrest at the S phase and apoptosis of NB cells.

Conclusions

Taken together, this study may shed light on new research areas for NB patients from the cuproptosis perspective.

Pro-metastatic and mesenchymal gene expression signatures characterize circulating tumor cells of neuroblastoma patients with bone marrow metastases and relapse

Existing marker-based methods of minimal residual disease (MRD) determination in neuroblastoma do not effectively enrich for the circulating disease cell population. Given the relative size differential of neuroblastoma tumor cells over normal hematogenous cells, we hypothesized that cell size-based separation could enrich circulating tumor cells (CTCs) from blood samples and disseminated tumor cells (DTCs) from bone marrow aspirates (BMA) of neuroblastoma patients, and that their gene expression profiles could vary dynamically with various disease states over the course of treatment. Using a spiral microfluidic chip, peripheral blood of 17 neuroblastoma patients at 3 serial treatment timepoints (diagnosis, n=17; post-chemotherapy, n=11; and relapse, n=3), and bone marrow samples at diagnosis were enriched for large intact circulating cells. Profiling the resulting enriched samples with immunohistochemistry and mRNA expression of 1490 cancer-related genes via NanoString, 13 of 17 samples contained CTCs displaying cytologic atypia, TH and PHOX2B expression and/or upregulation of cancer-associated genes. Gene signatures reflecting pro-metastatic processes and the neuroblastoma mesenchymal super-enhancer state were consistently upregulated in 7 of 13 samples, 6 of which also had metastatic high-risk disease. Expression of 8 genes associated with PI3K and GCPR signaling were significantly upregulated in CTCs of patients with bone marrow metastases versus patients without. Correspondingly, in patients with marrow metastases, differentially-expressed gene signatures reflected upregulation of immune regulation in bone marrow DTCs versus paired CTCs samples. In patients who later developed disease relapse, 5 genes involved in immune cell regulation, JAK/STAT signaling and the neuroblastoma mesenchymal super-enhancer state (OLFML2B, STAT1, ARHGDIB, STAB1, TLR2) were upregulated in serial CTC samples over their disease course, despite urinary catecholamines and bone marrow aspirates not indicating the disease recurrences. In summary, using a label-free cell size-based separation method, we enriched and characterized intact circulating cells in peripheral blood indicative of neuroblastoma CTCs, as well as their DTC counterparts in the bone marrow. Expression profiles of pro-metastatic genes in CTCs correlated with the presence of bone marrow metastases at diagnosis, while longitudinal profiling identified persistently elevated expression of genes in CTCs that may serve as novel predictive markers of hematogenous MRD in neuroblastoma patients that subsequently relapse.

Neuroblastic tumors and neurofibromatosis type 1: A retrospective multicenter study in Italy and systematic review of the literature

BACKGROUND

Neuroblastic tumors (NBTs) are the most common extra-cranial solid tumors of childhood. Neurofibromatosis type 1 (NF1) is the most common neurocutaneous disorder with a predisposition to tumors. The co-occurrence of NBTs in the setting of NF1 has been occasionally reported, suggesting a non-casual association and likely configuring a spectrum of neural crest-derived disorders.

AIM OF THE STUDY

To explore the occurrence of NBTs within NF1 and to report on its natural history, therapeutic strategies, and outcomes in an Italian cohort of children with NF1 and in the literature.

SUBJECTS AND METHODS

Study (a): a retrospective analysis of questionnaire-based data [years 1979-2017] derived from the databases of the Italian Registry for Neuroblastoma (RINB) of the Italian Society of Pediatric Onco-Haematology (AIEOP); and Study (b): a systematic review search on NF1/NB co-occurrence.

RESULTS

Study (a) identified eight children with NBTs, 0.2% of patients registered in the RINB, fulfilling the diagnostic criteria for NF1. The primary site of NBTs was abdominal in six patients. The NBTs were neuroblastoma (NB) in five patients, ganglioneuroblastoma (GNB) in one, patient, and ganglioneuroma (GN) in two. Metastatic diffusion occurred in three out of eight children. MYCN gene testing, performed in the tumors of five patients, resulted not-amplified. The major features of NF1 included the following: NF1 family history in four patients, café-au-lait spots in all, freckling in six, Lisch nodules in three, and neurofibromas in three. With regard to the outcome, four children survived three of these for the progression of NB and one for a second tumor. Study (b) identified 12 patients with NF1/NB from the years 1966-2017, and the median age at diagnosis was 27 months (range = 0-168 months). The primary site of NB was thoracic. The prevalent histotype was NB in nine patients, GNB in two, and GN in one. Eight/nine NBs were metastatic. The MYCN gene was amplified in the only studied case. The NF1 features included NF1 family history in seven patients; the major NF1 features were café-au-lait spots in nine patients, freckling in one, Lisch nodules in none, and neurofibromas in six. The outcome was good for only two children, while eight children died of neuroblastoma, at a median age of 49.5 months (range = 2.4-174 months), with a median survival time of 21.75 months after diagnosis.

CONCLUSIONS

To our knowledge, this represents the first systematic study on the occurrence of NBTs in NF1. This confirms that NBs are rare per se in the setting of NF1 (0.2% of all NBs) and even if compared to the overall frequency of malignancies in NF1 (i.e., 14.7%). The male:female ratio in study (a) (0.6) was different from what was recorded in study (b) (1.5) and in line with the overall increased frequency of malignancies in females with NF1. The median ages at diagnosis of NB in either study (a) or (b) were concordant with what occurred in the NB population. In study (a) versus study (b), the frequency of metastatic diffusion was lower, likely indicating less awareness on work-ups for malignancies in old NF1 series in the literature. The outcome was much better in study (a) than in study (b), indicating that multidisciplinary treatment for NB is highly recommended.

Neuroblastoma signalling models unveil combination therapies targeting feedback-mediated resistance

Very high risk neuroblastoma is characterised by increased MAPK signalling, and targeting MAPK signalling is a promising therapeutic strategy. We used a deeply characterised panel of neuroblastoma cell lines and found that the sensitivity to MEK inhibitors varied drastically between these cell lines. By generating quantitative perturbation data and mathematical modelling, we determined potential resistance mechanisms. We found that negative feedbacks within MAPK signalling and via the IGF receptor mediate re-activation of MAPK signalling upon treatment in resistant cell lines. By using cell-line specific models, we predict that combinations of MEK inhibitors with RAF or IGFR inhibitors can overcome resistance, and tested these predictions experimentally. In addition, phospho-proteomic profiling confirmed the cell-specific feedback effects and synergy of MEK and IGFR targeted treatment. Our study shows that a quantitative understanding of signalling and feedback mechanisms facilitated by models can help to develop and optimise therapeutic strategies. Our findings should be considered for the planning of future clinical trials introducing MEKi in the treatment of neuroblastoma.

Childhood cancer in Italy: background, goals, and achievements of the Italian Paediatric Hematology Oncology Association (AIEOP)

This article reviews the primary goals and achievements of the Italian Association for Pediatric Hematology-Oncology (Associazione Italiana Ematologia Oncologia Pediatrica [AIEOP]), a national cooperative group that has been working for children and adolescents with cancer in Italy since 1975.

Tailoring Therapy for Children With Neuroblastoma on the Basis of Risk Group Classification: Past, Present, and Future

For children with neuroblastoma, the likelihood of cure varies widely according to age at diagnosis, disease stage, and tumor biology. Treatments are tailored for children with this clinically heterogeneous malignancy on the basis of a combination of markers that are predictive of risk of relapse and death. Sequential risk-based, cooperative-group clinical trials conducted during the past 4 decades have led to improved outcome for children with neuroblastoma. Increasingly accurate risk classification and refinements in treatment stratification strategies have been achieved with the more recent discovery of robust genomic and molecular biomarkers. In this review, we discuss the history of neuroblastoma risk classification in North America and Europe and highlight efforts by the International Neuroblastoma Risk Group (INRG) Task Force to develop a consensus approach for pretreatment stratification using seven risk criteria including an image-based staging system-the INRG Staging System. We also update readers on the current Children's Oncology Group risk classifier and outline plans for the development of a revised 2021 Children's Oncology Group classifier that will incorporate INRG Staging System criteria to facilitate harmonization of risk-based frontline treatment strategies conducted around the globe. In addition, we discuss new approaches to establish increasingly robust, future risk classification algorithms that will further refine treatment stratification using machine learning tools and expanded data from electronic health records and the INRG Data Commons.

MicroRNAs in neuroblastoma tumorigenesis, therapy resistance, and disease evolution

Neuroblastoma (NB) deriving from neural crest cells is the most common extra-cranial solid cancer at infancy. NB originates within the peripheral sympathetic ganglia in adrenal medulla and along the midline of the body. Clinically, NB exhibits significant heterogeneity stretching from spontaneous regression to rapid progression to therapy resistance. MicroRNAs (miRNAs, miRs) are small (19-22 nt in length) non-coding RNAs that regulate human gene expression at the post-transcriptional level and are known to regulate cellular signaling, growth, differentiation, death, stemness, and maintenance. Consequently, the function of miRs in tumorigenesis, progression and resistance is of utmost importance for the understanding of dysfunctional cellular pathways that lead to disease evolution, therapy resistance, and poor clinical outcomes. Over the last two decades, much attention has been devoted to understanding the functional roles of miRs in NB biology. This review focuses on highlighting the important implications of miRs within the context of NB disease progression, particularly miRs’ influences on NB disease evolution and therapy resistance. In this review, we discuss the functions of both the “oncomiRs” and “tumor suppressor miRs” in NB progression/therapy resistance. These are the critical components to be considered during the development of novel miR-based therapeutic strategies to counter therapy resistance.

CXCR4 Promotes Neuroblastoma Growth and Therapeutic Resistance through miR-15a/16-1-Mediated ERK and BCL2/Cyclin D1 Pathways

CXCR4 expression in neuroblastoma tumors correlates with disease severity. In this study, we describe mechanisms by which CXCR4 signaling controls neuroblastoma tumor growth and response to therapy. We found that overexpression of CXCR4 or stimulation with CXCL12 supports neuroblastoma tumorigenesis. Moreover, CXCR4 inhibition with the high-affinity CXCR4 antagonist BL-8040 prevented tumor growth and reduced survival of tumor cells. These effects were mediated by the upregulation of miR-15a/16-1, which resulted in downregulation of their target genes BCL-2 and cyclin D1, as well as inhibition of ERK. Overexpression of miR-15a/16-1 in cells increased cell death, whereas antagomirs to miR-15a/16-1 abolished the proapoptotic effects of BL-8040. CXCR4 overexpression also increased miR-15a/16-1, shifting their oncogenic dependency from the BCL-2 to the ERK signaling pathway. Overall, our results demonstrate the therapeutic potential of CXCR4 inhibition in neuroblastoma treatment and provide a rationale to test combination therapies employing CXCR4 and BCL-2 inhibitors to increase the efficacy of these agents.Significance: These results provide a mechanistic rationale for combination therapy of CXCR4 and BCL-2 inhibitors to treat a common and commonly aggressive pediatric cancer.Cancer Res; 78(6); 1471-83. ©2017 AACR.

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.

Thymoquinone inhibits the migration of mouse neuroblastoma (Neuro-2a) cells by down-regulating MMP-2 and MMP-9

Thymoquinone (TQ), an active component derived from the medial plant Nigella sativa, has been used for medical purposes for more than 2 000 years. Recent studies have reported that TQ blocked angiogenesis in animal model and reduced migration, adhesion, and invasion of glioblastoma cells. We have recently shown that TQ could exhibit a potent cytotoxic effect and induce apoptosis in mouse neuroblastoma (Neuro-2a) cells. In the present study, TQ treatment markedly decreased the adhesion and migration of Neuro-2a cells. TQ down-regulated MMP-2 and MMP-9 protein expression and mRNA levels and their activities. Furthermore, TQ significantly down-regulated the protein expression of transcription factor NF-κB (p65) but not significantly altered the expression of N-Myc. Taken together, our data indicated that TQ's inhibitory effect on the migration of Neuro-2a cells was mediated through the suppression of MMP-2 and MMP-9 expression, suggesting that TQ treatment can be a promising therapeutic strategy for human malignant neuroblastoma.

Artificial neural network classifier predicts neuroblastoma patients' outcome

Background

More than fifty percent of neuroblastoma (NB) patients with adverse prognosis do not benefit from treatment making the identification of new potential targets mandatory. Hypoxia is a condition of low oxygen tension, occurring in poorly vascularized tissues, which activates specific genes and contributes to the acquisition of the tumor aggressive phenotype. We defined a gene expression signature (NB-hypo), which measures the hypoxic status of the neuroblastoma tumor. We aimed at developing a classifier predicting neuroblastoma patients’ outcome based on the assessment of the adverse effects of tumor hypoxia on the progression of the disease.

Methods

Multi-layer perceptron (MLP) was trained on the expression values of the 62 probe sets constituting NB-hypo signature to develop a predictive model for neuroblastoma patients’ outcome. We utilized the expression data of 100 tumors in a leave-one-out analysis to select and construct the classifier and the expression data of the remaining 82 tumors to test the classifier performance in an external dataset. We utilized the Gene set enrichment analysis (GSEA) to evaluate the enrichment of hypoxia related gene sets in patients predicted with “Poor” or “Good” outcome.

Results

We utilized the expression of the 62 probe sets of the NB-Hypo signature in 182 neuroblastoma tumors to develop a MLP classifier predicting patients’ outcome (NB-hypo classifier). We trained and validated the classifier in a leave-one-out cross-validation analysis on 100 tumor gene expression profiles. We externally tested the resulting NB-hypo classifier on an independent 82 tumors’ set. The NB-hypo classifier predicted the patients’ outcome with the remarkable accuracy of 87 %. NB-hypo classifier prediction resulted in 2 % classification error when applied to clinically defined low-intermediate risk neuroblastoma patients. The prediction was 100 % accurate in assessing the death of five low/intermediated risk patients. GSEA of tumor gene expression profile demonstrated the hypoxic status of the tumor in patients with poor prognosis.

Conclusions

We developed a robust classifier predicting neuroblastoma patients’ outcome with a very low error rate and we provided independent evidence that the poor outcome patients had hypoxic tumors, supporting the potential of using hypoxia as target for neuroblastoma treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s12859-016-1194-3) contains supplementary material, which is available to authorized users.

Lack of survival advantage with autologous stem-cell transplantation in high-risk neuroblastoma consolidated by anti-GD2 immunotherapy and isotretinoin

Since 2003, high-risk neuroblastoma (HR-NB) patients at our center received anti-G_D2 antibody 3F8/GM-CSF + isotretinoin – but not myeloablative therapy with autologous stem-cell transplantation (ASCT). Post-ASCT patients referred from elsewhere also received 3F8/GM-CSF + isotretinoin. We therefore accrued a study population of two groups treated during the same period and whose consolidative therapy, aside from ASCT, was identical. We analyzed patients enrolled in 1st complete/very good partial remission (CR/VGPR). Their event-free survival (EFS) and overall survival (OS) were calculated from study entry. Large study size allowed robust statistical analyses of key prognosticators including MYCN amplification, minimal residual disease (MRD), FCGR2A polymorphisms, and killer immunoglobulin-like receptor genotypes of natural killer cells. The 170 study patients included 60 enrolled following ASCT and 110 following conventional chemotherapy. The two cohorts had similar clinical and biological features. Five-year rates for ASCT and non-ASCT patients were, respectively: EFS 65% vs. 51% (p = .128), and OS 76% vs. 75% (p = .975). In multivariate analysis, ASCT was not prognostic and only MRD-negativity after two cycles of 3F8/GM-CSF correlated with significantly improved EFS and OS. Although a trend towards better EFS is seen with ASCT, OS is near identical. Cure rates may be similar, as close surveillance detects localized relapse and effective salvage treatments are applied. ASCT may not be needed to improve outcome when anti-G_D2 immunotherapy is used for consolidation after dose-intensive conventional chemotherapy.

Neuroblastoma (Peripheral neuroblastic tumours)

Peripheral neuroblastic tumours (PNTs), a family of tumours arising in the embryonal remnants of the sympathetic nervous system, account for 7-10% of all tumours in children. In two-thirds of cases, PNTs originate in the adrenal glands or the retroperitoneal ganglia. At least one third present metastases at onset, with bone and bone marrow being the most frequent metastatic sites. Disease extension, MYCN oncogene status and age are the most relevant prognostic factors, and their influence on outcome have been considered in the design of the recent treatment protocols. Consequently, the probability of cure has increased significantly in the last two decades. In children with localised operable disease, surgical resection alone is usually a sufficient treatment, with 3-year event-free survival (EFS) being greater than 85%. For locally advanced disease, primary chemotherapy followed by surgery and/or radiotherapy yields an EFS of around 75%. The greatest problem is posed by children with metastatic disease or amplified MYCN gene, who continue to do badly despite intensive treatments. Ongoing trials are exploring the efficacy of new drugs and novel immunological approaches in order to save a greater number of these patients.

Anticancer Activity of γ-Bisabolene in Human Neuroblastoma Cells via Induction of p53-Mediated Mitochondrial Apoptosis

γ-Bisabolene has demonstrated antiproliferative activities against several human cancer cell lines. This study first discloses the antiproliferative and apoptosis induction activities of γ-bisabolene to human neuroblastoma TE671 cells. A CC50 value of γ-bisabolene was 8.2 μM to TE671 cells. Cell cycle analysis with PI staining showed γ-bisabolene elevating the sub-G1 fractions in a time-dependent manner. In addition, annexin V-FITC/PI staining showed γ-bisabolene significantly triggering early (annexin-V positive/PI negative) and late (annexin-V positive/PI positive) apoptosis in dose-dependent manners. γ-Bisabolene induced caspase 3/8/9 activation, intracellular ROS increase, and mitochondrial membrane potential decrease in apoptosis of human neuro-blastoma cells. Moreover, γ-bisabolene increased p53 phosphorylation and up-regulated p53-mediated apoptotic genes Bim and PUMA, as well as decreased the mRNA and protein levels of CK2α. Notably, the results indicated the involvement of CK2α-p53 pathways in mitochondria-mediated apoptosis of human neuroblastoma cells treated with γ-bisabolene. This study elucidated the apoptosis induction pathways of γ-bisabolene-treated neuroblastoma cells, in which could be useful for developing anti-neuroblastoma drugs.

Autologous cord blood transplantation for metastatic neuroblastoma

Auto-SCT is a common approach for metastatic neuroblastoma with the intention to rescue hematopoiesis after megadose chemotherapy. PBSC or BM is the usual stem cell source for auto-SCT. Auto-CBT for neuroblastoma has very rarely been performed. Currently, case reports are available for two patients only. We performed 13 auto-SCTs for high-risk neuroblastoma from 2007 to 2013, including four cases of metastatic neuroblastoma aged 11-64 months treated with auto-CBT. All four patients had partial or CR to upfront treatments before auto-CBT. Nucleated cell dose and CD34+ cell dose infused were 2.8-8.7 × 10(7) /kg and 0.36-3.9 × 10(5) /kg, respectively. Post-thawed viability was 57-76%. Neutrophil engraftment (>0.5 × 10(9) /L) occurred at 15-33 days, while platelet engraftment occurred at 31-43 days (>20 × 10(9) /L) and 33-65 days (>50 × 10(9) /L) post-transplant, respectively. There was no severe acute or chronic complication. Three patients survived for 1.9-7.7 yr without evidence of recurrence. One patient relapsed at 16 months post-transplant and died of progressive disease. Cord blood may be a feasible alternative stem cell source for auto-SCT in patients with stage 4 neuroblastoma, and outcomes may be improved compared to autologous PBSC or BM transplants.

High-dose chemotherapy and autologous haematopoietic stem cell rescue for children with high-risk neuroblastoma

BACKGROUND

Despite the development of new treatment options, the prognosis of high-risk neuroblastoma patients is still poor; more than half of patients experience disease recurrence. High-dose chemotherapy and haematopoietic stem cell rescue (i.e. myeloablative therapy) might improve survival. This review is the second update of a previously published Cochrane review.

OBJECTIVES

Primary objectiveTo compare the efficacy, that is event-free and overall survival, of high-dose chemotherapy and autologous bone marrow or stem cell rescue with conventional therapy in children with high-risk neuroblastoma. Secondary objectivesTo determine adverse effects (e.g. veno-occlusive disease of the liver) and late effects (e.g. endocrine disorders or secondary malignancies) related to the procedure and possible effects of these procedures on quality of life.

SEARCH METHODS

We searched the electronic databases The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, issue 11), MEDLINE/PubMed (1966 to December 2014) and EMBASE/Ovid (1980 to December 2014). In addition, we searched reference lists of relevant articles and the conference proceedings of the International Society for Paediatric Oncology (SIOP) (from 2002 to 2014), American Society for Pediatric Hematology and Oncology (ASPHO) (from 2002 to 2014), Advances in Neuroblastoma Research (ANR) (from 2002 to 2014) and American Society for Clinical Oncology (ASCO) (from 2008 to 2014). We searched for ongoing trials by scanning the ISRCTN register (www.isrct.com) and the National Institute of Health Register (www.clinicaltrials.gov). Both registers were screened in April 2015.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the efficacy of myeloablative therapy with conventional therapy in high-risk neuroblastoma patients.

DATA COLLECTION AND ANALYSIS

Two authors independently performed study selection, data extraction and risk of bias assessment. If appropriate, we pooled studies. The risk ratio (RR) and 95% confidence interval (CI) was calculated for dichotomous outcomes. For the assessment of survival data, we calculated the hazard ratio (HR) and 95% CI. We used Parmar's method if hazard ratios were not reported in the study. We used a random-effects model.

MAIN RESULTS

We identified three RCTs including 739 children. They all used an age of one year as the cut-off point for pre-treatment risk stratification. The first updated search identified a manuscript reporting additional follow-up data for one of these RCTs, while the second update identified an erratum of this study. There was a significant statistical difference in event-free survival in favour of myeloablative therapy over conventional chemotherapy or no further treatment (three studies, 739 patients; HR 0.78, 95% CI 0.67 to 0.90). There was a significant statistical difference in overall survival in favour of myeloablative therapy over conventional chemotherapy or no further treatment (two studies, 360 patients; HR 0.74, 95% CI 0.57 to 0.98). However, when additional follow-up data were included in the analyses the difference in event-free survival remained statistically significant (three studies, 739 patients; HR 0.79, 95% CI 0.70 to 0.90), but the difference in overall survival was no longer statistically significant (two studies, 360 patients; HR 0.86, 95% CI 0.73 to 1.01). The meta-analysis of secondary malignant disease and treatment-related death did not show any significant statistical differences between the treatment groups. Data from one study (379 patients) showed a significantly higher incidence of renal effects, interstitial pneumonitis and veno-occlusive disease in the myeloablative group compared to conventional chemotherapy, whereas for serious infections and sepsis no significant difference between the treatment groups was identified. No information on quality of life was reported. In the individual studies we evaluated different subgroups, but the results were not univocal in all studies. All studies had some methodological limitations.

AUTHORS' CONCLUSIONS

Based on the currently available evidence, myeloablative therapy seems to work in terms of event-free survival. For overall survival there is currently no evidence of effect when additional follow-up data are included. No definitive conclusions can be made regarding adverse effects and quality of life, although possible higher levels of adverse effects should be kept in mind. A definitive conclusion regarding the effect of myeloablative therapy in different subgroups is not possible. This systematic review only allows a conclusion on the concept of myeloablative therapy; no conclusions can be made regarding the best treatment strategy. Future trials on the use of myeloablative therapy for high-risk neuroblastoma should focus on identifying the most optimal induction and/or myeloablative regimen. The best study design to answer these questions is a RCT. These RCTs should be performed in homogeneous study populations (e.g. stage of disease and patient age) and have a long-term follow-up. Different risk groups, using the most recent definitions, should be taken into account.It should be kept in mind that recently the age cut-off for high risk disease was changed from one year to 18 months. As a result it is possible that patients with what is now classified as intermediate-risk disease have been included in the high-risk groups. Consequently the relevance of the results of these studies to the current practice can be questioned. Survival rates may be overestimated due to the inclusion of patients with intermediate-risk disease.

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.

Prolonged progression-free survival after consolidating second or later remissions of neuroblastoma with Anti-GD2 immunotherapy and isotretinoin: a prospective Phase II study

Relapse of high-risk neuroblastoma (HR-NB) is deemed invariably fatal yet increasing numbers of HR-NB patients achieve a second complete/very good partial remission (CR/VGPR), hence the urgency to find a successful consolidative therapy. Identifying efficacy in patients without assessable disease, however, is problematic. We report the first study providing outcome data for this group of patients with poor prognosis. To prevent another relapse, HR-NB patients in second or later CR/VGPR received the anti-G_D2 murine antibody 3F8 plus granulocyte-macrophage colony-stimulating factor plus isotretinoin in a Phase II trial. Upon meeting the target aim for progression-free survival (PFS) in the initial cohort of 33 patients, the trial was amended to allow patients who developed human anti-mouse antibody (HAMA) to receive rituximab to ablate HAMA with or without low-dose maintenance chemotherapy until immunotherapy could resume. For the total of 101 study patients, 5-year PFS and overall survival (OS) rates were 33% ± 5% and 48% ± 5%, respectively. Among the 33 long-term progression-free survivors, 19 had MYCN amplification, 19 had previously received anti-G_D2 immunotherapy plus isotretinoin (as first-line therapy), and 15 never received maintenance chemotherapy. In a multivariate analysis of prognostic factors, only absence of minimal residual disease in bone marrow after 2 cycles of immunotherapy and before initiation of isotretinoin or anti-HAMA therapy was significantly favorable for both PFS and OS. Therefore, long-term PFS is possible for HR-NB patients who achieve at least a second CR/VGPR and receive consolidation that includes anti-G_D2 immunotherapy plus isotretinoin, even if the patients received these biological treatments before relapse. Results from this prospective study will aid in the development of future Phase II studies for this growing ultra high-risk patient population.

Rapid COJEC versus standard induction therapies for high-risk neuroblastoma

BACKGROUND

Neuroblastoma is a rare malignant disease and mainly affects infants and very young children. The tumors mainly develop in the adrenal medullary tissue and an abdominal mass is the most common presentation. The high-risk group is characterized by metastasis and other characteristics that increase the risk for an adverse outcome. In the rapid COJEC induction schedule, higher single doses of selected drugs than standard induction schedules are administered over a substantially shorter treatment period, with shorter intervals between cycles. Shorter intervals and higher doses increase the dose intensity of chemotherapy and might improve survival.

OBJECTIVES

The aim of this study was to evaluate the efficacy and adverse events of the rapid COJEC induction schedule as compared to standard induction schedules in patients with high-risk neuroblastoma (as defined by the International Neuroblastoma Risk Group (INRG) classification system). Outcomes of interest were complete response, early toxicity and treatment-related mortality as primary endpoints and overall survival, progression- and event-free survival, late non-hematological toxicity, and health-related quality of life as secondary endpoints.

SEARCH METHODS

We searched the electronic databases CENTRAL (2014, Issue 11), MEDLINE (PubMed), and EMBASE (Ovid) for articles from inception to 11 November 2014. Further searches included trial registries, conference proceedings, and reference lists of recent reviews and relevant articles. We did not apply limits on publication year or languages.

SELECTION CRITERIA

Randomized controlled trials evaluating the rapid COJEC induction schedule for high-risk neuroblastoma patients compared to standard induction schedules.

DATA COLLECTION AND ANALYSIS

Two review authors performed study selection, abstracted data on study and patient characteristics, and assessed risk of bias independently. We resolved differences by discussion or by appeal to a third review author. We performed analyses according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions. We used the five GRADE considerations, study limitations, consistency of effect, imprecision, indirectness, and publication bias, to judge the quality of the evidence. We downgraded for risk of bias and imprecision

MAIN RESULTS

We identified one randomized controlled trial (CCLG-ENSG-5) that included 262 patients with high-risk neuroblastoma who were randomized to receive either rapid COJEC (N = 130) or standard OPEC/COJEC (N = 132) induction chemotherapy. We graded the evidence as low quality; we downgraded for risk of bias and imprecision.There was no clear evidence of a difference between the treatment groups in complete response (risk ratio (RR) 0.99, 95% confidence interval (CI) 0.71 to 1.38), treatment-related mortality (RR 1.21, 95% CI 0.33 to 4.39), overall survival (hazard ratio (HR) 0.83, 95% CI 0.63 to 1.10), and event-free survival (HR 0.86, 95% CI 0.65 to 1.13). We calculated the HRs using the complete follow-up period of the trial.Febrile neutropenia (two or more episodes), proven fungal infections, septicemia (one or more episodes), gastrointestinal toxicity (grade 3 or 4), renal toxicity (glomerular filtration rate < 80 ml/min per body surface area of 1.73 m(2)), neurological toxicity (grade 3 or 4), and ototoxicity (Brock grade 2 to 4) were addressed as early toxicities (during pre-operative chemotherapy). For febrile neutropenia, septicemia, and renal toxicity, a statistically significant difference in favor of the standard treatment arm was identified; for all other early toxicities no clear evidence of a difference between treatment groups was identified. With regard to late non-hematological toxicities (median follow-up 12.7 years; range 6.9 to 16.5 years), the study provided data on any complication, renal toxicity (glomerular filtration rate < 80 ml/min per body surface area of 1.73m(2)), ototoxicity (Brock grade 1 to 4), endocrine complications, neurocognitive complications (i.e. behavioral, speech, or learning difficulties), and second malignancies. For endocrine complications and neurocognitive complications, a statistically significant difference in favor of the rapid COJEC arm was found; for all other late non-hematological toxicities no clear evidence of a difference between treatment groups was identified.Data on progression-free survival and health-related quality of life were not reported.

AUTHORS' CONCLUSIONS

We identified one randomized controlled trial that evaluated rapid COJEC versus standard induction therapy in patients with high-risk neuroblastoma. No clear evidence of a difference in complete response, treatment-related mortality, overall survival, and event-free survival between the treatment alternatives was found. This could be the result of low power or too short a follow-up period. Results of both early and late toxicities were ambiguous. Information on progression-free survival and health-related quality of life were not available. This trial was performed in the 1990s. Since then, many changes in, for example, treatment and risk classification have occurred. Therefore, based on the currently available evidence, we are uncertain about the effects of rapid COJEC and standard induction therapy in patients with high-risk neuroblastoma. More research is needed for a definitive conclusion.

The novel anti-neuroblastoma agent PF403, inhibits proliferation and invasion in vitro and in brain xenografts

Neuroblastoma is the most common cancer in infants and the fourth most common cancer in children. Our previous study showed that PF403 had a potent antitumor ability. In the present study, we evaluated the anti-neuroblastoma property of PF403 and investigated the underlying mechanisms. MTT assay, colony formation assay and flow cytometry assay were used to assess cytotoxicity of PF403 on SH-SY5Y cells. Transwell assay was chosen to estimate the anti-invasion ability of PF403 on neuroblastoma cells. The protein expression was detected by western blot analysis. The SH-SY5Y brain xenograft model was used to assess in vivo antitumor activity of PF403. PF403-mediated SH-SY5Y cell death was found to be dose- and time-dependent, and PF403 was able to limit invasion and metastasis of neuroblastoma cells. MRI and pathology analysis proved that the pro-drug of PF403, CAT3, inhibited SH-SY5Y cells in vivo. PF403 decreased expression of phosphorylated FAK, MMP-2 and MMP-9 proteins, and downregulated the activity of PI3K/AKT and Raf/ERK pathways, followed by regulation of the proteins expression of Bcl-2 family, activated caspase-3, -9 and PARP and initiation of apoptosis of neuroblastoma cells. PF403 exerted cytotoxicity against SH-SY5Y neuroblastoma cell both in vitro and in vivo, and inhibited its invasion ability, suggesting PF403 has potential as a new anticancer drug for the treatment of neuroblastoma.

Outcomes After Radiation Therapy to Metastatic Sites in Patients With Stage 4 Neuroblastoma

In patients with high-risk metastatic neuroblastoma, the benefit of radiation therapy (RT) to metastatic sites as part of primary treatment has not been fully investigated. The purpose of this single-institution study was to evaluate local control of irradiated metastatic sites, and characterize metastatic disease burden and anatomic distribution in patients with high-risk metastatic neuroblastoma. The records of all patients diagnosed with stage 4 neuroblastoma between August 2000 and January 2010 were reviewed. Exclusion criteria included: bone-marrow only metastatic site, total body irradiation, or no imaging follow-up. A total of 37 patients met eligibility criteria. Median follow-up period for patients without relapse was 61 months. Five-year overall survival for all patients was 67%. Thirteen patients (35%) received RT to a metastatic site as part of their primary treatment. Among these patients, in-field recurrence occurred in three patients (23%), including two of three treated calvarial sites. In patients treated with or without RT to a metastatic site, respectively, there was no significant difference in 5-year overall survival (73% vs. 63%, P=0.84) or relapse-free survival (46% and 55%, P=0.48). Current metastatic site RT dose may be suboptimal, and certain locations may predict for a poor response. Further studies are necessary to elucidate the optimal role of RT to metastatic sites.

Additional Therapies to Improve Metastatic Response to Induction Therapy in Children With High-risk Neuroblastoma

Children with high-risk neuroblastoma who fail to achieve adequate metastatic response after induction chemotherapy have dismal outcome and new therapeutic strategies are needed. However, timing of introduction of novel agents still remains under discussion. Given an increase in number of phase I-II studies of molecularly targeted drugs in neuroblastoma, it is crucial to determine, as early as possible, which patients may be suitable candidates for new therapeutic strategies. This single-center retrospective analysis of patients with high-risk neuroblastoma showed that the addition of conventional chemotherapy improved the quality of metastatic response only for the group of patients with partial response. It is therefore proposed to develop stratification criteria for those patients very unlikely to benefit from a plethora of additional lines of treatment, but might benefit from introduction of novel agents.

Quantitative nuclear proteomics identifies that miR-137-mediated EZH2 reduction regulates resveratrol-induced apoptosis of neuroblastoma cells

Neuroblastoma is the most common pediatric extracranial solid tumor with a broad spectrum of clinical behavior and poor prognosis. Despite intensive multimodal therapy, ongoing clinical trials, and basic science investigations, neuroblastoma remains a complex medical challenge with a long-term survival rate less than 40%. In our study, we found that resveratrol (3, 5, 4'-trihydroxystilbene, RSV), a naturally occurring phytoalexin, possesses an anticancer activity through blocking cell growth and inducing apoptosis in neuroblastoma cell line Neuro-2a (N-2a) cells. Using stable isotope labeling with amino acids in cell culture (SILAC) and quantitative proteomic analysis, we found that 395 proteins were up-regulated and 302 proteins were down-regulated in the nucleus of N-2a cells treated with RSV. Among these, the polycomb protein histone methyltransferase EZH2 was reduced significantly, which is aberrantly overexpressed in neuroblastoma and crucial to maintain the malignant phenotype of neuroblastoma by epigenetic repression of multiple tumor suppressor genes. EZH2 reduction further led to decreased H3K27me3 level and reactivation of neuroblastoma tumor suppressor genes CLU and NGFR. Disruption EZH2 expression by RNA interference-mediated knockdown or pharmacologic inhibition with DZNep triggered cellular apoptosis in N-2a cells. We found that the up-regulation of miR-137 level was responsible for reduced EZH2 level in tumor suppression induced by RSV. Inhibition of miR-137 expression rescued the cellular apoptosis phenotypes, EZH2 reduction, and CLU and NGFR reactivation, associated with RSV treatment. Taken together, our findings present for the first time, an epigenetic mechanism involving miR-137-mediated EZH2 repression in RSV-induced apoptosis and tumor suppression of neuroblastoma, which would provide a key potential therapeutic target in neuroblastoma treatment.

Ga-68 DOTATATE positron emission tomography/computer tomography in initial staging and therapy response evaluation in a rare case of primary neuroblastoma in neck

Gallium-68 (Ga-68) DOTA-peptide positron emission tomography/computer tomography (PET/CT) has higher sensitivity and improved spatial resolution for the detection of somatostatin receptor expressing tumors than conventional somatostatin receptor scintigraphy. We present the findings of Ga-68 DOTATATE PET/CT in a rare case of primary neuroblastoma of the neck in a 12-year-old female child and its role in the evaluation of the treatment response.

Treatment including anthracyclines versus treatment not including anthracyclines for childhood cancer

BACKGROUND

One of the most important adverse effects of anthracyclines is cardiotoxicity. A well-informed decision on the use of anthracyclines in the treatment of childhood cancers should be based on evidence regarding both antitumour efficacy and cardiotoxicity. This review is the second update of a previously published Cochrane review.

OBJECTIVES

To compare antitumour efficacy (survival and tumour response) and cardiotoxicity of treatment including or not including anthracyclines in children with childhood cancer.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2013, Issue 6), MEDLINE (1966 to July 2013) and EMBASE (1980 to July 2013). In addition, we searched reference lists of relevant articles and conference proceedings, the International Society for Paediatric Oncology (SIOP) (from 2002 to 2012) and American Society of Clinical Oncology (ASCO) (from 2002 to 2013). We have searched for ongoing trials in the ISRCTN register and the National Institute of Health register (both screened August 2013) (http://www.controlled-trials.com).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing treatment of any type of childhood cancer with and without anthracyclines and reporting outcomes concerning antitumour efficacy or cardiotoxicity.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed the study selection, risk of bias assessment and data extraction. Analyses were performed according to the guidelines of the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We identified RCTs for seven types of tumour, acute lymphoblastic leukaemia (ALL) (three trials; 912 children), Wilms' tumour (one trial; 316 children), rhabdomyosarcoma and undifferentiated sarcoma (one trial; 413 children), Ewing's sarcoma (one trial; 94 children), non-Hodgkin lymphoma (one trial; 284 children), hepatoblastoma (one trial; 255 children) and acute myeloid leukaemia (AML) (one trial; 394 children). All studies had methodological limitations. For ALL no evidence of a significant difference in antitumour efficacy was identified in the meta-analyses, but in most individual studies there was a suggestion of better antitumour efficacy in patients treated with anthracyclines. For both Wilms' tumour and Ewing's sarcoma a significant difference in event-free and overall survival in favour of treatment with anthracyclines was identified, although for Wilms' tumour the significant difference in overall survival disappeared with long-term follow-up. For rhabdomyosarcoma and undifferentiated sarcoma, non-Hodgkin lymphoma and hepatoblastoma no difference in antitumour efficacy between the treatment groups was identified. The same was true for AML, with the exception of overall survival in a post hoc analysis in a subgroup of patients with relapsed core binding factor (CBF)-AML in which patients treated with anthracyclines did better. Clinical cardiotoxicity was evaluated in four RCTs; no significant difference between the treatment groups was identified, but in all individual studies there was a suggestion of a lower rate of clinical cardiotoxicity in patients who did not receive anthracyclines. None of the studies evaluated asymptomatic cardiac dysfunction. No RCTs were identified for other childhood cancers.

AUTHORS' CONCLUSIONS

At the moment no evidence from RCTs is available which underscores the use of anthracyclines in ALL. However, 'no evidence of effect', as identified in this review, is not the same as 'evidence of no effect'. For Wilms' tumour, rhabdomyosarcoma and undifferentiated sarcoma, Ewing's sarcoma, non-Hodgkin lymphoma, hepatoblastoma and AML only one RCT was available for each type and, therefore, no definitive conclusions can be made about the antitumour efficacy of treatment with or without anthracyclines in these tumours. For other childhood cancers no RCTs were identified and therefore no conclusions can be made about the antitumour efficacy of treatment with or without anthracyclines in these tumours.

Neuroblastoma: outcome over a 14 year period from a tertiary care referral centre in India

PURPOSE

To evaluate the outcome of children with neuroblastoma (NB) from a tertiary care referral centre in India.

METHOD

All children with NB registered from October 1996 through July 2009 were included in the study. INSS was used for staging. All children included in the study received chemotherapy and radiation therapy appropriate for stage. Tumor resection was done when feasible. The final outcome was overall survival and it was categorized as Complete Response (CR), Partial Response (PR); No Response (NR) and Progressive Disease (PD). Analysis of three-year overall survival was done using Kaplan Meier method and Log Rank test of significance. Multivariate analysis for significance of age, site and stage was performed.

RESULTS

144 children in the age range of 1-132months (median 36) were enrolled. Only 38 (26.4%) children were below 12months. 112 (77.8%) of the tumors were abdominal and 32 (22.2%) were extra-abdominal. Stage distribution was 1+2 in 6 (4.2%); 3 in 58 (40.3%); 4 in 68 (47.2%); 4s in 12 (8.3%). 83 (57.6%) underwent gross complete resection. At the time of last follow-up, 100 (69.4%) were alive [60 CR (41.7%); 33 PR; 7 PD/NR] and 44 (30.6%) were dead [1CR; 11PR; 32 PD/NR]. The three-year OS was 60.7% [95 CI 50.4-69.5]. The OS was 69.7% for those<12months of age [95 CI 51.8-82.0] and CR was achieved in 57.9%, while for those >12months the OS was 55.3% [95 CI 42.2-66.6] and CR was achieved in 35.8% (p=0.73). All 6 (100%) patients with Stage 1 and Stage 2 disease were alive and disease free. The OS was 71.5% for Stage 3[95 CI 55.3-82.7] and CR was achieved in 56.9%, while for Stage 4 the OS was 35.7%[95 CI 19.3-52.4] and CR was achieved in 17.6% (p=0.001). The OS was 83.3% for 4s [95 CI 48.2-95.6] and CR was achieved in 75%.

CONCLUSION

All the six children with Stage 1 & 2 achieved CR and were alive, while 57% of Stage 3 could achieve CR and had an OS of 71.5%. The OS (35.7%) and CR (17.6%) for Stage 4 were significantly less (p=0.001).

Flotillin-1 regulates oncogenic signaling in neuroblastoma cells by regulating ALK membrane association

Neuroblastomas harbor mutations in the nonreceptor anaplastic lymphoma kinase (ALK) in 8% to 9% of cases where they serve as oncogenic drivers. Strategies to reduce ALK activity offer clinical interest based on initial findings with ALK kinase inhibitors. In this study, we characterized phosphotyrosine-containing proteins associated with ALK to gain mechanistic insights in this setting. Flotillin-1 (FLOT1), a plasma membrane protein involved in endocytosis, was identified as a binding partner of ALK. RNAi-mediated attenuation of FLOT1 expression in neuroblastoma cells caused ALK dissociation from endosomes along with membrane accumulation of ALK, thereby triggering activation of ALK and downstream effector signals. These features enhanced the malignant properties of neuroblastoma cells in vitro and in vivo. Conversely, oncogenic ALK mutants showed less binding affinity to FLOT1 than wild-type ALK. Clinically, lower expression levels of FLOT1 were documented in highly malignant subgroups of human neuroblastoma specimens. Taken together, our findings suggest that attenuation of FLOT1-ALK binding drives malignant phenotypes of neuroblastoma by activating ALK signaling.

Striking dichotomy in outcome of MYCN-amplified neuroblastoma in the contemporary era

BACKGROUND

The authors exploited a large database to investigate the outcomes of patients with high-risk neuroblastoma in the contemporary era.

METHODS

All patients with high-risk neuroblastoma aged <12 years who were treated during induction at the authors' institution from 2000 through 2011 were studied, including 118 patients with MYCN-amplified [MYCN(+)] disease and 127 patients aged >18 months with MYCN-nonamplified [MYCN(-)] stage 4 disease.

RESULTS

A complete response/very good partial response (CR/VGPR) to induction was correlated with significantly superior event-free survival (EFS) (P < .001) and overall survival (OS) (P < .001) compared with a partial response or less. Patients with MYCN(+) and MYCN(-) disease had similar rates of CR/VGPR to induction (P = .366), and those with MYCN(+) and MYCN(-) disease who attained a CR/VGPR had similar EFS (P = .346) and OS (P = .542). In contrast, only MYCN(+) patients had progressive disease as a response to induction (P < .001), and early death from progressive disease (<366 days after diagnosis) was significantly more common (P < .001) among those with MYCN(+) disease. Overall, among patients who had a partial response or less, MYCN(+) patients had significantly inferior EFS (P < .001) and OS (P < .001) compared with MYCN(-) patients, which accounted for the significantly worse EFS (P = .008) and OS (P = .002) for the entire MYCN(+) cohort versus the MYCN(-) cohort.

CONCLUSIONS

Patients with MYCN(-), high-risk neuroblastoma display a broad, continuous spectrum with regard to response and outcome, whereas MYCN(+) patients either have an excellent response to induction associated with good long-term outcome or develop early progressive disease with a poor outcome. This extreme dichotomy in the clinical course of MYCN(+) patients points to underlying biologic differences with MYCN(+) neuroblastoma, the elucidation of which may have far-reaching implications, including improved risk classification at diagnosis and the identification of targets for treatment.

Nr4a3, a possibile oncogenic factor for neuroblastoma associated with CpGi methylation within the third exon

Aberrant methylation of Nr4a3 exon 3 CpG island (CpGi) was initially identified during multistep mouse skin carcinogenesis. Nr4a3 is also known as a critical gene for neuronal development. Thus, we examined the Nr4a3 exon 3 CpGi methylation in mouse brain tissues from 15-day embryos, newborns and 12-week-old adults and found significant increase of its methylation and Nr4a3 expression during mouse brain development after birth. In addition, homologous region in human genome was frequently and aberrantly methylated in neuroblastoma specimens. A quantitative analysis of DNA methylation revealed that hypomethylation of CpG islands on NR4A3 exon 3, but not on exon 1 was identified in three neuroblastomas compared with matched adrenal glands. Additional analysis for 20 neuroblastoma patients was performed and 8 of 20 showed hypomethylation of the CpGi on NR4A3 exon 3. The survival rate of those 8 patients was significantly lower compared with those in patients with hypermethylation. Immunohistochemical NR4A3 expression was generally faint in neuroblastoma tissues compared with normal tissues. Moreover, the MYCN amplified NB9 cell line showed hypomethylation and low expression of NR4A3, while the non-MYCN amplified NB69 cell line showed hypermethylation and high expression. These results indicate that DNA hypomethylation of the CpGi at NR4A3 exon 3 is associated with low NR4A3 expression, and correlates with poor prognosis of neuroblastoma. Since NR4A3 upregulation associated with the hypermethylation and neuronal differentiation in mice, poor prognosis of neuroblastoma associated with NR4A3 low expression may be partly explained by dysregulation of its differentiation.

Antiangiogenic effect of propranolol on the growth of the neuroblastoma xenografts in nude mice

BACKGROUND

Propranolol has been reported to display an antiangiogenic effect on infantile hemangiomas and also some adult cancers. Little is known, however, about whether propranolol has such effect on pediatric malignancies.

METHODS

Nude mice bearing BE(2) C neuroblastoma xenografts were injected intraperitoneally with propranolol and divided into groups of PROP-2 (n=11), -5 (n=11), and -10 (n=10) according to the treating dosages of 2, 5, and 10 mg kg(-1) day(-1), respectively. The tumor volume and body weight were recorded every other day. All mice were sacrificed on day 9, and the levels of angiogenic factors were measured in harvested xenografts by immunohistochemistry and western blotting.

RESULTS

The tumor volume and weight of PROP-2 (0.72±0.28 cm(3), 0.59±0.21 g) and PROP-5 (0.81±0.35 cm(3), 0.61±0.25 g) were significantly decreased when compared with those of CTL (1.22±0.58 cm(3), 0.93±0.15 g; P<0.01). The tumor microvessel density (MVD) scores that PROP-2, -5, and -10 groups had (49.28±17.53, 52.45±17.11, and 51.09±13.18 pixels per picture, respectively) were lower than those from the control group (65.29±17.33 pixels per picture, P<0.01). Furthermore, vascular endothelial growth factor (VEGF), metalloproteinase-2 (MMP-2), and metalloproteinase-9 (MMP-9) levels were significantly lower in the groups with propranolol treated dosage of 5 and 10 mg kg(-1)day(-1) than in the control group.

CONCLUSIONS

Propranolol can exhibit an inhibitory effect on the tumor growth and angiogenic factors expression in neuroblastoma xenografts, which may provide some knowledge to the role of β-blockers in the management of NB.

High-dose chemotherapy and autologous haematopoietic stem cell rescue for children with high-risk neuroblastoma

BACKGROUND

Despite the development of new treatment options, the prognosis of high-risk neuroblastoma patients is still poor; more than half of patients experience disease recurrence. High-dose chemotherapy and haematopoietic stem cell rescue (i.e. myeloablative therapy) might improve survival. This review is an update of a previously published Cochrane review.

OBJECTIVES

The primary objective was to compare the efficacy of myeloablative therapy with conventional therapy in children with high-risk neuroblastoma. Secondary objectives were to determine possible effects of these interventions on adverse events, late effects and quality of life.

SEARCH METHODS

We searched the electronic databases CENTRAL (The Cochrane Library 2012, issue 6), MEDLINE/PubMed (1966 to June 2012) and EMBASE/Ovid (1980 to June 2012). In addition, we searched reference lists of relevant articles and the conference proceedings of the International Society for Paediatric Oncology (SIOP) (from 2002 to 2011), American Society for Pediatric Hematology and Oncology (ASPHO) (from 2002 to 2012), Advances in Neuroblastoma Research (ANR) (from 2002 to 2012) and American Society for Clinical Oncology (ASCO) (from 2008 to 2012). We searched for ongoing trials by scanning the ISRCTN register and the National Institute of Health Register (http://www.controlled-trials.com; both screened July 2012).

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing the efficacy of myeloablative therapy with conventional therapy in high-risk neuroblastoma patients.

DATA COLLECTION AND ANALYSIS

Two authors independently performed study selection, data extraction and risk of bias assessment. If appropriate, we pooled studies. The risk ratio (RR) and 95% confidence interval (CI) was calculated for dichotomous outcomes. For the assessment of survival data, we calculated the hazard ratio (HR) and 95% CI. We used Parmar's method if hazard ratios were not reported in the study. We used a random-effects model.

MAIN RESULTS

We identified three RCTs including 739 children. They all used an age of one year as the cut-off point for pre-treatment risk stratification. The updated search identified a manuscript reporting additional follow-up data for one of these RCTs. There was a statistically significant difference in event-free survival in favour of myeloablative therapy over conventional chemotherapy or no further treatment (3 studies, 739 patients; HR 0.78, 95% CI 0.67 to 0.90). There was a statistically significant difference in overall survival in favour of myeloablative therapy over conventional chemotherapy or no further treatment (2 studies, 360 patients; HR 0.74, 95% CI 0.57 to 0.98). However, when additional follow-up data were included in the analyses the difference in event-free survival remained statistically significant (3 studies. 739 patients; HR 0.79, 95% CI 0.70 to 0.90), but the difference in overall survival was no longer statistically significant (2 studies, 360 patients; HR 0.86, 95% CI 0.73 to 1.01). The meta-analysis of secondary malignant disease and treatment-related death did not show any statistically significant differences between the treatment groups. Data from one study (379 patients) showed a significantly higher incidence of renal effects, interstitial pneumonitis and veno-occlusive disease in the myeloablative group compared to conventional chemotherapy, whereas for serious infections and sepsis no significant difference between the treatment groups was identified. No information on quality of life was reported. In the individual studies we evaluated different subgroups, but the results were not univocal in all studies. All studies had some methodological limitations.

AUTHORS' CONCLUSIONS

Based on the currently available evidence, myeloablative therapy seems to work in terms of event-free survival. For overall survival there is currently no evidence of effect when additional follow-up data are included. No definitive conclusions can be made regarding adverse effects and quality of life, although possible higher levels of adverse effects should be kept in mind. A definitive conclusion regarding the effect of myeloablative therapy in different subgroups is not possible. This systematic review only allows a conclusion on the concept of myeloablative therapy; no conclusions can be made regarding the best treatment strategy. Future trials on the use of myeloablative therapy for high-risk neuroblastoma should focus on identifying the most optimal induction and/or myeloablative regimen. The best study design to answer these questions is a RCT. These RCTs should be performed in homogeneous study populations (e.g. stage of disease and patient age) and have a long-term follow-up. Different risk groups, using the most recent definitions, should be taken into account.It should be kept in mind that recently the age cut-off for high risk disease was changed from one year to 18 months. As a result it is possible that patients with what is now classified as intermediate-risk disease have been included in the high-risk groups. Consequently the relevance of the results of these studies to the current practice can be questioned. Survival rates may be overestimated due to the inclusion of patients with intermediate-risk disease.

LIMK2 mediates resistance to chemotherapeutic drugs in neuroblastoma cells through regulation of drug-induced cell cycle arrest

Drug resistance is a major obstacle for the successful treatment of many malignancies, including neuroblastoma, the most common extracranial solid tumor in childhood. Therefore, current attempts to improve the survival of neuroblastoma patients, as well as those with other cancers, largely depend on strategies to counter cancer cell drug resistance; hence, it is critical to understand the molecular mechanisms that mediate resistance to chemotherapeutics. The levels of LIM-kinase 2 (LIMK2) are increased in neuroblastoma cells selected for their resistance to microtubule-targeted drugs, suggesting that LIMK2 might be a possible target to overcome drug resistance. Here, we report that depletion of LIMK2 sensitizes SHEP neuroblastoma cells to several microtubule-targeted drugs, and that this increased sensitivity correlates with enhanced cell cycle arrest and apoptosis. Furthermore, we show that LIMK2 modulates microtubule acetylation and the levels of tubulin Polymerization Promoting Protein 1 (TPPP1), suggesting that LIMK2 may participate in the mitotic block induced by microtubule-targeted drugs through regulation of the microtubule network. Moreover, LIMK2-depleted cells also show an increased sensitivity to certain DNA-damage agents, suggesting that LIMK2 might act as a general pro-survival factor. Our results highlight the exciting possibility of combining specific LIMK2 inhibitors with anticancer drugs in the treatment of multi-drug resistant cancers.

Long-term follow-up of children with high-risk neuroblastoma: the ENSG5 trial experience

BACKGROUND

Therapy for high-risk neuroblastoma is intensive and multimodal, and significant long-term adverse effects have been described. The aim of this study was to identify the nature and severity of late complications of metastatic neuroblastoma survivors included in the ENSG5 clinical trial.

PROCEDURE

The trial protocol included induction chemotherapy (randomized "Standard" OPEC/OJEC vs. "Rapid" COJEC), surgery of primary tumor and high-dose melphalan with stem cell rescue. Two hundred and sixty-two children were randomized, 69 survived >5 years, and 57 were analyzed. Data were obtained from the ENSG5 trial database and verified with questionnaires sent to participating centers.

RESULTS

Median follow-up was 12.9 (6.9-16.5) years. No differences were found in late toxicities between treatment arms. Twenty-eight children (49.1%) developed hearing loss. Nine patients (15.8%) developed glomerular filtration rate <80 ml/min/1.73 m(2), but no cases of chronic renal failure were documented. Endocrine complications (28.1% of children) included mainly hypogonadism and delayed growth. Four children developed second malignancies, three of them 5 years after diagnosis: one osteosarcoma, one carcinoma of the parotid gland and one ependymoma. There were no hematological malignancies or deaths in remission.

CONCLUSIONS

This study analyzed a wide cohort of high-risk neuroblastoma survivors from a multi-institutional randomized trial and established the profile of long-term toxicity within the setting of an international clinical trial.

MicroRNA-497 increases apoptosis in MYCN amplified neuroblastoma cells by targeting the key cell cycle regulator WEE1

Background

Neuroblastoma is responsible for 15% of all childhood cancer deaths. Despite advances in treatment and disease management, the overall 5-year survival rates remain poor in high-risk disease (25-40%). MiR-497 was previously identified by our laboratory as a member of a miRNA expression signature, predictive of neuroblastoma patient survival and has been reported as a tumor suppressor in a variety of other cancers. WEE1, a tyrosine kinase regulator of the cell cycle and predicted target of miR-497, has emerged as an oncogene in several cancer types and therefore represents an attractive potential target for novel therapy approaches in high-risk neuroblastoma. Our aim was to investigate the potential tumor suppressive role of miR-497 in high-risk neuroblastoma.

Methods

Expression levels of miR-497 and WEE1 in tissues and cells were determined using RT-PCR. The effect of miR-497 and siWEE1 on cell viability was evaluated using MTS assays, apoptosis levels were determined using FACS analysis of Annexin V/PI stained cells, and target protein expression was determined using western blot. Luciferase reporter plasmids were constructed to confirm direct targeting. Results were reported as mean±S.E.M and differences were tested for significance using 2-tailed Students t-test.

Results

We determined that miR-497 expression was significantly lower in high-risk MYCN amplified (MNA) tumors and that low miR-497 expression was associated with worse EFS and OS in our cohort. Over-expression of miR-497 reduced cell viability and increased apoptosis in MNA cells. We identified WEE1 as a novel target for miR-497 in neuroblastoma. Furthermore, our analysis showed that high WEE1 levels are significantly associated with poor EFS and OS in neuroblastoma and that siRNA knockdown of WEE1 in MNA cell lines results in significant levels of apoptosis, supporting an oncogenic role of WEE1 in neuroblastoma. Cisplatin (CDDP) treatment of both miR-497 over-expressing cells and WEE1 inhibited cells, resulted in a significant increase in apoptosis in MNA cells, describing a synergistic effect and therefore a potential therapeutic for high-risk neuroblastoma.

Conclusion

Our study’s results are consistent with miR-497 being a candidate tumor suppressor in neuroblastoma, through the direct targeting of WEE1. These findings re-enforce the proposal of WEE1 as a therapeutic target in neuroblastoma.

CDK4 inhibition restores G(1)-S arrest in MYCN-amplified neuroblastoma cells in the context of doxorubicin-induced DNA damage

Relapse with drug-resistant disease is the main cause of death in MYCN-amplified neuroblastoma patients. MYCN-amplified neuroblastoma cells in vitro are characterized by a failure to arrest at the G(1)-S checkpoint after irradiation- or drug-induced DNA damage. We show that several MYCN-amplified cell lines harbor additional chromosomal aberrations targeting p53 and/or pRB pathway components, including CDK4/CCND1/MDM2 amplifications, p16INK4A/p14ARF deletions or TP53 mutations. Cells with these additional aberrations undergo significantly lower levels of cell death after doxorubicin treatment compared with MYCN-amplified cells, with no additional mutations in these pathways. In MYCN-amplified cells CDK4 expression is elevated, increasing the competition between CDK4 and CDK2 for binding p21. This results in insufficient p21 to inhibit CDK2, leading to high CDK4 and CDK2 kinase activity upon doxorubicin treatment. CDK4 inhibition by siRNAs, selective small compounds or p19(INK4D) overexpression partly restored G(1)-S arrest, delayed S-phase progression and reduced cell viability upon doxorubicin treatment. Our results suggest a specific function of p19(INK4D), but not p16(INK4A), in sensitizing MYCN-amplified cells with a functional p53 pathway to doxorubicin-induced cell death. In summary, the CDK4/cyclin D-pRB axis is altered in MYCN-amplified cells to evade a G(1)-S arrest after doxorubicin-induced DNA damage. Additional chromosomal aberrations affecting the p53-p21 and CDK4-pRB axes compound the effects of MYCN on the G(1) checkpoint and reduce sensitivity to cell death after doxorubicin treatment. CDK4 inhibition partly restores G(1)-S arrest and sensitizes cells to doxorubicin-mediated cell death in MYCN-amplified cells with an intact p53 pathway.

Thiotepa and melphalan based single, tandem, and triple high dose therapy and autologous stem cell transplantation for high risk neuroblastoma

BACKGROUND

Outcome of high risk neuroblastoma (NBL) remains unsatisfactory in spite of intensive treatment efforts. Consolidation with high-dose (HD) chemotherapy and autologous stem cell transplantation (ASCT) has been intensified with tandem and triple cycles with promising results. Our purpose was to improve the outcome with two or three HD-consolidations.

METHODS

Thirty six children with high risk NBL, diagnosed 1995-2010, had intensive induction and surgery, and were stratified to single, tandem or triple HD-therapy and ASCT, followed by local irradiation and cis-retinoic acid. In inoperable patients surgery was facilitated by preoperative HD-melphalan. Long-term outcome of our old cohort from 1987-1994 was updated.

RESULTS

Ten year event-free survival (EFS) from diagnosis was 0.44+/-0.10 of the old and 0.43+/-0.085 of the new cohort. EFS from the last ASCT was 0.53 +/-0.12 and 0.48+/-0.091, respectively. Preoperative HD-melphalan rendered 73% of bulky primaries operable in the new cohort. The 5-yr EFS from ASCT was 0.46+/-0.15 for single and 0.73+/-0.15 for tandem ASCT (P = 0.19). All triple ASCT patients, selected by poor/slow response, relapsed or died.

CONCLUSIONS

Thiotepa- and melphalan based HD regimens, with or without total body irradiation (TBI), appeared to give an outcome comparable to major NBL study groups with acceptable toxicity. Tandem HD therapy gave a 5-year EFS of 73%, whereas a third HD consolidation did not offer any additional advantage for ultra high risk patients with slow response. Pediatr Blood Cancer 2012; 59: 1190-1197. © 2012 Wiley Periodicals, Inc.

Reversible adaptive plasticity: a mechanism for neuroblastoma cell heterogeneity and chemo-resistance

We describe a novel form of tumor cell plasticity characterized by reversible adaptive plasticity in murine and human neuroblastoma. Two cellular phenotypes were defined by their ability to exhibit adhered, anchorage dependent (AD) or sphere forming, anchorage independent (AI) growth. The tumor cells could transition back and forth between the two phenotypes and the transition was dependent on the culture conditions. Both cell phenotypes exhibited stem-like features such as expression of nestin, self-renewal capacity, and mesenchymal differentiation potential. The AI tumorspheres were found to be more resistant to chemotherapy and proliferated slower in vitro compared to the AD cells. Identification of specific molecular markers like MAP2, β-catenin, and PDGFRβ enabled us to characterize and observe both phenotypes in established mouse tumors. Irrespective of the phenotype originally implanted in mice, tumors grown in vivo show phenotypic heterogeneity in molecular marker signatures and are indistinguishable in growth or histologic appearance. Similar molecular marker heterogeneity was demonstrated in primary human tumor specimens. Chemotherapy or growth factor receptor inhibition slowed tumor growth in mice and promoted initial loss of AD or AI heterogeneity, respectively. Simultaneous targeting of both phenotypes led to further tumor growth delay with emergence of new unique phenotypes. Our results demonstrate that neuroblastoma cells are plastic, dynamic, and may optimize their ability to survive by changing their phenotype. Phenotypic switching appears to be an adaptive mechanism to unfavorable selection pressure and could explain the phenotypic and functional heterogeneity of neuroblastoma.

Emerging treatment options for the treatment of neuroblastoma: potential role of perifosine

Achieving a cure for high-risk neuroblastoma, the most common extracranial solid tumor in children, remains a formidable task despite the recent addition of antibody-mediated anti-GD2 immunotherapy to established multimodality therapy. The PI3K/Akt pathway is a pivotal signaling pathway utilized by a plethora of receptor tyrosine kinases that contribute to the aggressive phenotype of high-risk neuroblastoma. Akt is aberrantly activated in high-risk neuroblastoma and is therefore an attractive therapeutic target. Perifosine is the best-characterized Akt inhibitor in preclinical studies and in clinical trials in adults, although safety in children is not yet confirmed. It is a synthetic third-generation alkylphospholipid with good oral bioavailability and modest side effects. Perifosine targets the lipid-binding PH domain of Akt and inhibits the translocation of Akt to the cell membrane, an essential step for Akt activation. It decreases Akt phosphorylation and increases caspase-dependent apoptosis in neuroblastoma cell lines, inhibits growth of neuroblastoma xenografts, and overcomes RTK/ligand-mediated chemoresistance. It is currently being studied in two Phase I clinical trials in children with recurrent or refractory solid tumors including neuroblastoma. In the single agent trial (ClinicalTrials.gov identifier NCT00776867), maximum tolerated dose has not yet been reached and pharmacokinetic data has been accrued. In the second study (ClinicalTrials.gov identifier NCT01049841), patients are treated with a combination of perifosine and the mTOR-inhibitor temsirolimus based on preclinical data showing synergy of the two agents, and the premise that direct Akt inhibition may overcome Akt activation secondary to mTOR inhibition. Based on results from adult trials, it is unlikely that perifosine alone will produce dramatic therapeutic effects against high-risk neuroblastoma. However, given the recent encouraging early-phase combination therapy results in adults with multiple myeloma and colorectal carcinoma, rational perifosine-containing combination regimens hold promise for neuroblastoma therapy. These will be explored after safety in children is established in Phase I studies.

Tandem stem cell rescue as consolidation therapy for high-risk neuroblastoma

BACKGROUND

Despite aggressive treatment for high-risk neuroblastoma (NB), event-free survival (EFS) remains <40%. In single arm studies, intensifying therapy with high-dose chemotherapy and tandem autologous stem cell rescue (HDC/SCR) improved outcome. We retrospectively describe our institutional experience in using HDC/SCR for patients with high-risk NB, focusing on outcome and acute toxicities.

METHODS

Eighty-four patients with high-risk NB at Children's Healthcare of Atlanta treated over a 12-year time period underwent HDC/SCR as part of upfront therapy; 28 patients received a single HDC/SCR and 56 patients received tandem HDC/SCR. The two groups were compared in terms of EFS, overall survival (OS), and acute transplant related toxicities.

RESULTS

Patients who received tandem HDC/SCR had a significantly improved EFS compared with patients who received a single HDC/SCR (4-year EFS 59.3 ± 6.7% vs. 26.8 ± 9.2%, P=0.01). Similarly, the 4-year OS was improved in patients receiving tandem HDC/SCR, though this did not reach statistical significance (70.6 ± 9.2% vs. 44.7±11.2%, P=0.06). Multivariate regression confirmed the prognostic role of the treatment group. None of the patients who underwent a single HDC/SCR developed veno-occlusive disease (VOD), while 17% of patients who underwent tandem HDC/SCR developed mild-to-severe VOD. Rates of other transplant-related acute toxicities were similar.

CONCLUSION

Tandem HDC/SCR for patients with high-risk NB seems to improve survival without significant increases in acute toxicities. This needs to be validated in randomized prospective trials.

Synergistic effects of combination treatment with bortezomib and doxorubicin in human neuroblastoma cell lines

BACKGROUND

Neuroblastoma (NB) is the most common extracranial solid tumor in infants. Currently, the mainstay of NB chemotherapy is combination treatment with some traditional drugs, but these combination regimens are always inefficient.

METHODS

The aim of this study was to evaluate the inhibitory effect of a combination of doxorubicin and bortezomib, a novel anticancer drug and the first prote-asome inhibitor approved for the treatment of human malignant tumors, on the proliferation of two human NB cell lines, SK-N-SH and SH-SY5Y. The general mechanism underlying this combined effect was also investigated. Synergistic inhibitory effects on human NB cell proliferation were evaluated using the median-effect principle. The pro-apoptotic effects of these drugs were evaluated using double staining with annexin-V-FITC and propidium iodide.

RESULTS

Synergistic inhibitory effects on proliferation were observed when a combination of bortezomib and doxorubicin was applied to cultured NB cells. A similar synergistic effect on apoptosis was also observed when the two drugs were used concurrently, which suggested that the possible mechanism underlying the observed synergistic inhibitory effect might be related to apoptosis.

CONCLUSION

The combination of bortezomib and doxorubicin appears to be a promising strategy to treat NB.

Aberrant activation of ALK kinase by a novel truncated form ALK protein in neuroblastoma

Anaplastic lymphoma kinase (ALK) was originally identified from a rare subtype of non-Hodgkin's lymphomas carrying t(2;5)(p23;q35) translocation, where ALK was constitutively activated as a result of a fusion with nucleophosmin (NPM). Aberrant ALK fusion proteins were also generated in inflammatory fibrosarcoma and a subset of non-small-cell lung cancers, and these proteins are implicated in their pathogenesis. Recently, ALK has been demonstrated to be constitutively activated by gene mutations and/or amplifications in sporadic as well as familial cases of neuroblastoma. Here we describe another mechanism of aberrant ALK activation observed in a neuroblastoma-derived cell line (NB-1), in which a short-form ALK protein (ALK(del2-3)) having a truncated extracellular domain is overexpressed because of amplification of an abnormal ALK gene that lacks exons 2 and 3. ALK(del2-3) was autophosphorylated in NB-1 cells as well as in ALK(del2-3)-transduced cells and exhibited enhanced in vitro kinase activity compared with the wild-type kinase. ALK(del2-3)-transduced NIH3T3 cells exhibited increased colony-forming capacity in soft agar and tumorigenicity in nude mice. RNAi-mediated ALK knockdown resulted in the growth suppression of ALK(del2-3)-expressing cells, arguing for the oncogenic role of this mutant. Our findings provide a novel insight into the mechanism of deregulation of the ALK kinase and its roles in neuroblastoma pathogenesis.

Simultaneous diagnosis of acute lymphoblastic leukemia and peripheral neuroblastic tumor in a child

We report the case of a 3-year-old girl with a mediastinal mass, severe anemia, leukocytosis and neutropenia, in whom, after initial suspicion of metastatic neuroblastoma, a final diagnosis of concurrent ganglioneuroblastoma and acute lymphoblastic leukemia was made. The mediastinal tumor was surgically excised and the child subsequently underwent chemotherapy for acute lymphoblastic leukemia. The patient remains in complete remission from both diseases 4 years after the diagnosis and 24 months after completion of all treatment. The simultaneous occurrence of 2 different neoplasms in a child is very infrequent, and no comparable cases are reported in the literature.

Gene expression of TRK neurotrophin receptors in advanced neuroblastomas in Singapore--a pilot study

The clinical hallmark of neuroblastoma is heterogeneity. Biologically, ploidy and N-Myc amplification are currently the only 2 features used to define risk group and to determine therapy. Tyrosine kinase neurotrophin receptors (Trks, including TrkA, TrkB, and TrkC) are important in the clinical and biological behavior of neuroblastomas. The authors aim to study Trks gene expression in their local population of advanced neuroblastoma patients. Multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) assay on the expression of TrkA, TrkB, TrkB-truncated, and TrkC was performed on a total of 19 advanced neuroblastoma archival tumors, diagnosed in KK Women's and Children's Hospital between 2003 and 2007. Of the 19 tumors investigated, Trks expression was present in 14 (73.6%) cases. Of these cases, 8 (42.1%), 10 (52.6%), 7 (36.8%), and 6 (31.6%) expressed TrkA, TrkB, TrkB-truncated, and TrkC receptor mRNAs, respectively. Subsequently, the authors compared Trks expression with N-Myc amplification status of the 19 patients. N-Myc was amplified in 5 (26.3%) of the cases. Within the non-N-Myc-amplified group, Trks expression was present in 9 (64%) of the 14 cases. The significant expression of Trk isoforms among advanced neuroblastoma cases as evident from this study support their role as possible risk assessment tools alongside N-Myc amplification status.

Survival and late effects in children with stage 4 neuroblastoma

BACKGROUND

Treatment of metastatic neuroblastoma (NB) demands aggressive oncological therapy, which may cause long-term sequelae in survivors. The aim of this retrospective single center study is to give an overview of survival in children with stage 4 NB and to describe the spectrum of late effects seen in survivors.

PROCEDURE

Medical records of 31 patients with stage 4 NB treated between 1984 and 2009, who were included in a follow-up programme, were reviewed for information on tumor, treatment and late effects.

RESULTS

Five-year overall survival was 54.3 ± 9% and 5-year event-free survival was 44.9 ± 9%. Patients diagnosed after 1996 had a significantly better survival rate than those diagnosed before (74 ± 11.2% vs. 33.3 ± 12.2%, P = 0.011). In 15 of the 16 survivors (93.8%), numerous late effects were detected. The most common long-term sequelae were renal changes in 10 patients (62.5%) and endocrine disturbances in 9 patients (56.3%), including hypothyroidism with need of substitution in 50%, GH deficiency in 37.5% and hypogonadism in 12.5%. Sensorineural hearing loss occurred in 37.5% of survivors. Further observed late effects were hepatobiliary changes (31.3%), musculoskeletal problems, and pulmonary abnormalities (each 25%), as well as neurologic changes (18.8%), dental defects (12.5%), and unilateral blindness (6.3%). Second neoplasms appeared in 3 patients, 1 of whom died of hepatocellular carcinoma following infection with hepatitis B.

CONCLUSIONS

More than 50% of children with stage 4 NB may survive. The high incidence of severe long-term sequelae underlines the importance of careful follow-up in order to detect and treat late effects early enough.