Neuroblastoma after childhood: prognostic relevance of segmental chromosome aberrations, ATRX protein status, and immune cell infiltration

Adolescent- and adult-onset neuroblastic tumor: A retrospective multicenter observational study of patients diagnosed in France between 2000 and 2020

BACKGROUND

Adult- and adolescent-onset neuroblastomas are rare, with no established therapy. In addition, rare pheochromocytomas may harbor neuroblastic components. This study was designed to collect epidemiological, diagnostic and therapeutic data in order to better define the characteristics of malignant peripheral neuroblastic tumors (MPNT) and composite pheochromocytomas (CP) with MPNT.

PROCEDURE

Fifty-nine adults and adolescents (aged over 15 years) diagnosed with a peripheral or composite neuroblastic tumor, who were treated in one of 17 institutions between 2000 and 2020, were retrospectively studied.

RESULTS

Eighteen patients with neuroblastoma (NB) or ganglioneuroblastoma (GNB) had locoregional disease, and 28 patients had metastatic stage 4 NB. Among the 13 patients with CP, 12 had locoregional disease. Fifty-eight percent of the population were adolescents and young adults under 24 years of age. The probability of 5-year event-free survival (EFS) was 40% (confidence interval: 27%-53%).

CONCLUSIONS

Outcomes were better for patients with localized tumor than for patients with metastases. For patients with localized tumor, in terms of survival, surgical treatment was the best therapeutic option. Multimodal treatment with chemotherapy, surgery, radiotherapy, and immunotherapy-based maintenance allowed long-term survival for some patients. Adolescent- and adult-onset neuroblastoma appeared to have specific characteristics associated with poorer outcomes compared to pediatric neuroblastoma. Nevertheless, complete disease control improved survival. The presence of a neuroblastic component in pheochromocytoma should be considered when making therapeutic management decisions. The development of specific tools/resources (Tumor Referral Board, Registry, biology, and trials with new agents or strategies) may help to improve outcomes for patients.

17q Gain in Neuroblastoma: A Review of Clinical and Biological Implications

Neuroblastoma (NB) is the most frequent extracranial solid childhood tumor. Despite advances in the understanding and treatment of this disease, the prognosis in cases of high-risk NB is still poor. 17q gain has been shown to be the most frequent genomic alteration in NB. However, the significance of this remains unclear because of its high frequency and association with other genetic modifications, particularly segmental chromosomal aberrations, 1p and 11q deletions, and MYCN amplification, all of which are also associated with a poor clinical prognosis. This work reviewed the evidence on the clinical and biological significance of 17q gain. It strongly supports the significance of 17q gain in the development of NB and its importance as a clinically relevant marker. However, it is crucial to distinguish between whole and partial chromosome 17q gains. The most important breakpoints appear to be at 17q12 and 17q21. The former distinguishes between whole and partial chromosome 17q gain; the latter is a site of IGF2BP1 and NME1 genes that appear to be the main oncogenes responsible for the functional effects of 17q gain.

Molecular genomic landscape of pediatric solid tumors in Chinese patients: implications for clinical significance

PURPOSE

Pediatric solid tumors are significantly different from adult tumors. Studies have revealed genomic aberrations in pediatric solid tumors, but these analyses were based on Western populations. Currently, it is not known to what extent the existing genomic findings represent differences in ethnic backgrounds.

EXPERIMENTAL

DESIGN: We retrospectively analyzed the basic clinical characteristics of the patients, including age, cancer type, and sex distribution, and further analyzed the somatic and germline mutations of cancer-related genes in a Chinese pediatric cohort. In addition, we investigated the clinical significance of genomic mutations on therapeutic, prognostic, diagnostic, and preventive actions.

RESULTS

Our study enrolled 318 pediatric patients, including 234 patients with CNS tumors and 84 patients with non-CNS tumors. Somatic mutation analysis showed that there were significant differences in mutation types between CNS tumors and non-CNS tumors. P/LP germline variants were identified in 8.49% of patients. In total, 42.8% patients prompted diagnostic, 37.7% patients prompted prognostic, 58.2% patients prompted therapeutic, and 8.5% patients prompted tumor-predisposing and preventive, and we found that genomic findings might improve clinical management.

CONCLUSIONS

Our study is the first large-scale study to analyze the landscape of genetic mutations in pediatric patients with solid tumors in China. Genomic findings in CNS and non-CNS solid pediatric tumors provide evidence for the clinical classification and individualized treatment of pediatric tumors, and they will facilitate improvement of clinical management. Data presented in this study should serve as a reference to guide the future design of clinical trials.

Early-phase clinical trial eligibility and response evaluation criteria for refractory, relapsed, or progressive neuroblastoma: A consensus statement from the National Cancer Institute Clinical Trials Planning Meeting

BACKGROUND

International standardized criteria for eligibility, evaluable disease sites, and disease response assessment in patients with refractory, progressive, or relapsed high-risk neuroblastoma enrolled in early-phase clinical trials are lacking.

METHODS

A National Cancer Institute-sponsored Clinical Trials Planning Meeting was convened to develop an international consensus to refine the tumor site eligibility criteria and evaluation of disease response for early-phase clinical trials in children with high-risk neuroblastoma.

RESULTS

Standardized data collection of patient and disease characteristics (including specified genomic data), eligibility criteria, a definition of evaluable disease, and response evaluations for primary and metastatic sites of disease were developed. Eligibility included two distinct patient groups: progressive disease and refractory disease. The refractory disease group was subdivided into responding persistent disease and stable persistent disease to better capture the clinical heterogeneity of refractory neuroblastoma. Requirements for defining disease evaluable for a response assessment were provided; they included requirements for biopsy to confirm viable neuroblastoma and/or ganglioneuroblastoma in those patients with soft tissue or bone disease not avid for iodine-123 meta-iodobenzylguanidine. Standardized evaluations for response components and time intervals for response evaluations were established.

CONCLUSIONS

The use of international consensus eligibility, evaluability, and response criteria for early-phase clinical studies will facilitate the collection of comparable data across international trials and promote more rapid identification of effective treatment regimens for high-risk neuroblastoma.

Macrophage-mediated anti-tumor immunity against high-risk neuroblastoma

Neuroblastoma is the most common extracranial childhood solid tumor. The majority of high-risk neuroblastoma is resistant/refractory to the current high intensity therapy. Neuroblastoma lacks classical HLA Class I expression and exhibits low mutation burden, allowing neuroblastoma cells to evade CD8+ T cell-mediated immunity. Neuroblastoma cells do not express PD-L1, and tumor-associated macrophages are the predominant PD-L1+ cells in the tumor. In this study, we performed gene expression profiling and survival analyses on large neuroblastoma datasets to address the prognostic effect of PD-L1 gene expression and the possible involvement of the SLAMF7 pathway in the anti-neuroblastoma immunity. High-level expression of PD-L1 was found significantly associated with better outcome of high-risk neuroblastoma patients; two populations of PD-1+ PD-L1+ macrophages could be present in high-risk tumors with PD-1/PD-L1 ratios, ≈1 and >1. Patients with the PD-1/PD-L1 ratio >1 tumor showed inferior survival. High-level co-expression of SLAMF7 and SH2D1B was significantly associated with better survival of the high-risk neuroblastoma patients. Together, this study supports the hypothesis that macrophages are important effector cells in the anti-high-risk neuroblastoma immunity, that PD-1 blockade therapy can be beneficial to the high-risk neuroblastoma subset with the PD-1/PD-L1 expression ratio >1, and that SLAMF7 is a new therapeutic target of high-risk neuroblastoma.

Targeting Oncogenic Transcriptional Networks in Neuroblastoma: From N-Myc to Epigenetic Drugs

Neuroblastoma (NB) is one of the most frequently occurring neurogenic extracranial solid cancers in childhood and infancy. Over the years, many pieces of evidence suggested that NB development is controlled by gene expression dysregulation. These unleashed programs that outline NB cancer cells make them highly dependent on specific tuning of gene expression, which can act co-operatively to define the differentiation state, cell identity, and specialized functions. The peculiar regulation is mainly caused by genetic and epigenetic alterations, resulting in the dependency on a small set of key master transcriptional regulators as the convergence point of multiple signalling pathways. In this review, we provide a comprehensive blueprint of transcriptional regulation bearing NB initiation and progression, unveiling the complexity of novel oncogenic and tumour suppressive regulatory networks of this pathology. Furthermore, we underline the significance of multi-target therapies against these hallmarks, showing how novel approaches, together with chemotherapy, surgery, or radiotherapy, can have substantial antineoplastic effects, disrupting a wide variety of tumorigenic pathways through combinations of different treatments.

Low Protein Expression of both ATRX and ZNRF3 as Novel Negative Prognostic Markers of Adult Adrenocortical Carcinoma

Adrenocortical carcinoma (ACC) is a rare malignancy that is associated with a dismal prognosis. Pan-genomic studies have demonstrated the involvement of ATRX and ZNRF3 genes in adrenocortical tumorigenesis. Our aims were to evaluate the protein expression of ATRX and ZNRF3 in a cohort of 82 adults with ACC and to establish their prognostic value. Two pathologists analyzed immuno-stained slides of a tissue microarray. The low protein expression of ATRX and ZNRF3 was associated with a decrease in overall survival (OS) (p = 0.045, p = 0.012, respectively). The Cox regression for ATRX protein expression of >1.5 showed a hazard ratio (HR) for OS of 0.521 (95% CI 0.273-0.997; p = 0.049) when compared with ≤1.5; for ZNRF3 expression >2, the HR for OS was 0.441 (95% CI, 0.229-0.852; p = 0.015) when compared with ≤2. High ATRX and ZNRF3 protein expressions were associated with optimistic recurrence-free survival (RFS) (p = 0.027 and p = 0.005, respectively). The Cox regression of RFS showed an HR of 0.332 (95%CI, 0.111-0.932) for ATRX expression >2.7 (p = 0.037), and an HR of 0.333 (95%CI, 0.140-0.790) for ZNRF3 expression >2 (p = 0.013). In conclusion, low protein expression of ATRX and ZNRF3 are negative prognostic markers of ACC; however, different cohorts should be evaluated to validate these findings.

Typical numerical alterations in genome identified by array CGH analysis in neuroblastoma tumors

<abstract><sec> <title>Introduction</title> <p>The clinical variability in the course of neuroblastoma (NB) is closely linked to diverse genetic changes acquired by tumor cells. Rapid NB progression is associated with oncogene MYCN amplification (MNA) and segmental chromosomal aberrations (SCA). Alternatively, numerical chromosomal alterations (NCA) have positive impact on treatment. So far, no studies have been undertaken to identify NCA that may group NB patients. Therefore, the aim of the study was to identify NCA typical for NB.</p> </sec><sec> <title>Materials and methods</title> <p>Copy number alterations in NB tumor genome (fresh samples N = 94; formalin-fixed paraffin-embedded specimens N = 66) were analyzed with a pangenomic array CGH technique.</p> </sec><sec> <title>Results</title> <p>The profile with NCA was observed in 72 (45%) cases, NCA+SCA in 37 (23%), normal in 35 (22%) and MNA in 16 (10%). Samples with NCA were characterized by whole chromosome gains: 17, 7, 6 (78%, 65%, 51%, respectively) and copy loss of chromosome 14 (57%). Similarly to NCA, patients with a combined NCA and SCA profile were also characterized by gain of whole chromosome 17 and 7 (35% both) and loss of chromosome 14 (38%), but with lower frequency. In the combined NCA and SCA profiles, typical NB changes such as deletion 1p36 (27%) and gain 17q (41%) were observed, as well as deletion 11q (24%). The same alterations were detected in MNA samples (44%, 44%, 19%, respectively). A difference was found in spanning 11q deletion between MNA and NCA+SCA subgroup, which may suggest new prognostic markers in NB. In MNA subgroup specific NCA was not indicated.</p> </sec><sec> <title>Conclusions</title> <p>The hypothesis that NCA in NB tumors are more frequent in younger children with good prognosis was confirmed. To gain new insights into the pathogenesis of NB and to establish molecular targets for diagnosis and therapy, candidate genes in the altered chromosomal regions must be investigated.</p> </sec></abstract>

The glycosphingolipid GD2 as an effective but enigmatic target of passive immunotherapy in children with aggressive neuroblastoma (HR-NBL)

Neuroblastoma (NBL), the most frequent and lethal pediatric cancer of children in pre-school age, is considered enigmatic in view of its extreme heterogeneity, from spontaneous regression in the IV-S form to incurable disease in approx. 40% of cases (High Risk, HR-NBL). It has an embryonal origin and a very heterogeneous genomic landscape, hampering the success of targeted strategies. The glycosphingolipid GD2 was shown to be expressed on NBL cells and utilized as target for passive immunotherapy with anti-GD2 antibodies (GD2-IMT). An international protocol was established with GD2-IMT, which increases remission length and survival in HR-NBL. By reviewing the different biological and molecular aspects of NBL and GD2-IMT, this mini-review questions the present lack of association between GD2-IMT and the underlying molecular landscape. The alternative model of Micro-Foci inducing virus (MFV) is presented, since MFV infection can induce extensive genomic aberrations (100X NMYC DNA-amplification). Since this family of viruses uses molecules for cell penetration similar to GD2 (i.e., GM2), it is hypothesized that GD2 is the port-of-entry for MFV and that success of anti-GD2 therapies is also associated to inhibition of this clastogenic virus in HR-NBL.

19p loss is significantly enriched in older age neuroblastoma patients and correlates with poor prognosis

Genomic aberrations of neuroblastoma occurring in late childhood and adolescence are still understudied. Publicly available DNA copy number profiles of 556 tumors (discovery set) and of 208 tumors obtained by array-CGH assay (validation set) were used to test if 19p loss is significantly over-represented in children and adolescents with neuroblastoma. The 19p loss occurrence was separately tested within different age groups in the discovery and validation set and the resulting P values were combined by meta-analysis and corrected by Bonferroni's method. In both sets, 19p loss was associated with older age at diagnosis. Particularly, the lowest age group significantly associated with 19p loss (discovery set: 20%; validation set: 35%) was 6 years. The 19p loss correlated with inferior overall survival in patients over 6 years of age. Relevant tumor suppressor genes (KEAP1, DNM2, SMARCA4, SLC44A2 and CDKN2D) and microRNAs (miR-181c, miR-27a, and mirR-199a-1) are located in the genomic region involved in 19p loss. Downregulation of DNM2, SLC44A2 and CDKN2D was associated with poor patient outcome and older age. Among the recurrent NB chromosomal aberrations, only 1q gain was enriched in patients older than 6, and its presence was mutually exclusive with respect to 19p loss. Our data demonstrate that 19p loss is a genomic biomarker of NB diagnosed in older children that can predict clinical outcome.

[Cancer in the first 18 months of life]

INTRODUCTION

Oncological-haematological disease continues to be the first cause of non-traumatic mortality in childhood, as well as a significant cause of morbidity. The patient less than 18-months-old has special clinical, diagnostic, and therapeutic features that all paediatricians are interested in determining, with the aim of achieving greater survival and a lower morbidity throughout the lives of their patients.

MATERIAL AND METHODS

A retrospective, descriptive study was carried out using the clinical, diagnostic, and therapeutic variables in patients less than 18-months-old diagnosed with an oncological-haematological that received chemotherapy in a Paediatric Oncology Unit between January 2007 and August 2019.

RESULTS

A total of 72 patients were diagnosed with 76 cancers that required chemotherapy. The most common cancer was leukaemia (21 patients), followed by neuroblastoma (15 patients), and tumours of the central nervous system (12 patients). The presentation of "life-threatening symptoms" was seen in 20.8% of cases, particularly in tumours of neural origin (13/15). Although 18% of patients showed no symptoms on diagnosis, just over half (51%) of the diagnoses took place in the "advanced stages". Particularly in the case of solid tumours in which 23.6% were diagnosed with metastases. A significant percentage of genetic alterations implicated in the aetiopathogenesis of the different cancers were found.

CONCLUSIONS

Cancer in the first stages of life is a diagnostic and therapeutic challenge due to its phenotypical diversity, its genetic load, and its therapeutic difficulties. Knowledge of its particular features is essential for its early and effective approach.

Immunohistochemistry for ATRX Can Miss ATRX Mutations: Lessons From Neuroblastoma

Neuroblastoma is the most common extracranial solid tumor of childhood with a median age of presentation of 17 months. A common theme in high-risk neuroblastoma is maintenance of telomeres, one mechanism for which involves alternate lengthening of telomeres (ALT) associated with ATRX gene mutations. Mutations are believed to result in loss of ATRX protein, and therefore immunohistochemistry is used to detect mutations. We screened 133 cases of neuroblastoma by ATRX immunohistochemistry, and found 9 cases with partial to total absence of ATRX. Sequencing for ATRX mutations detected a mutation in 1 of 9 cases, suggesting immunostaining was not reliable for detecting mutations. To correlate immunostaining with ALT, fluorescence in situ hybridization (FISH) for ALT was performed in 6 of these cases and 5 (from 4 patients) showed ALT, implying impaired ATRX protein function, despite the failure to identify a mutation. Two other cases with large deletions in the ATRX gene showed diffusely positive staining for ATRX protein but showed ALT by FISH. Four of the 6 patients with ALT-positive tumors were over 5 years old. Therefore, 29 additional patients 5 years old and above with ATRX-positive tumors were screened for ALT by FISH and 6 additional cases with ALT were detected, bringing the total to 29% (10/34) of children 5 years old and above, 70% of which showed positive ATRX immunohistochemistry. Patients with ATRX mutations in neuroblastoma tend to have a more chronic and progressive course of disease. Screening neuroblastoma tumors at diagnosis for ATRX mutations may help identify patients who might benefit from personalized therapy directed against ALT. However, relaying on negative immunohistochemistry for ATRX protein to identify ALT in neuroblastoma may miss a significant proportion of patients. The addition of FISH for ALT as part of the diagnostic workup, especially for older children (5 y old and above), would help ensure that patients are correctly identified for anti-ALT therapy.

Neuroblastoma in Adolescents and Children Older than 10 Years: Unusual Clinicopathologic and Biologic Features

Neuroblastoma (NB) in children older than 10 years is rare. We reviewed our archives for patients with NB aged 10 to 18 years and summarized their clinicopathologic/genetic records. Of 96 patients, 4 patients were identified in this age group. Four tumors were abdominal; 1 patient had 2 tumors at diagnosis, one of which was presacral. Tumor sizes ranged from 3 to 20 cm. All tumors were high risk at clinical stages 3 and 4, with metastasis to bone marrow and other areas. Four tumors were poorly differentiated with unfavorable histology and one patient with bilateral adrenal disease had an intermixed ganglioneuroblastoma on one side. Another tumor exhibited pheochromocytoma-like morphology. MYCN amplification was present in bone marrow metastasis in one case. Complex chromosomal gains and 19p deletions were common. Exome sequencing revealed ALK variants in 2 cases and previously unreported MAGI2, RUNX1, and MLL mutations. All patients received standard chemotherapy and 2 patients received ALK-targeted trial therapy. Three patients died of disease, ranging 18 to 23 months after diagnosis. One patient has active disease and is receiving trial therapy. In conclusion, NB in children older than 10 years may exhibit unusual clinicopathologic and genetic features with large tumors, bilateral adrenal disease, rare morphologic features, complex DNA microarray findings and novel mutations. Patients often have grim prognoses despite genomic profiling-guided targeted therapy.

State of the art in immunotherapy of neuroblastoma

Neuroblastoma (NB) is a common and deadly malignancy mostly observed in children. Evolution of therapeutic options for NB led to the addition of immunotherapeutic modalities to the previously recruited chemotherapeutic options. Molecular studies of the NB cells resulted in the discovery of many tumor-associated genes and antigens such as MYCN gene and GD2. MYCN gene and GD2 surface antigen are two of the most practical discoveries regarding immunotherapy of neuroblastoma. The GD2 antigen has been targeted in many animal and human studies including Phase III clinical trials. Even though these antigens have changed the face of pediatric neuroblastoma, they do not take as much credit in immunotherapy of adult-onset neuroblastoma. Monoclonal antibodies have been designed to detect this antigen on the surface of NB tumor cells. Despite bettering the outcomes for NB patients, current therapies still fail in many cases. Studies are underway to discover more specific tumor-associated antigens and more effective treatment options. In the current narrative, immunotherapy of NB - from emerging of this therapeutic backbone in NB to the latest discoveries regarding this malignancy - has been reviewed.

Adult neuroblastoma: a rare diagnosis of an adrenal mass

A 22-year-old woman presented to her local district hospital with left-sided abdominal pain. She denied any urinary or gastrointestinal symptoms. She had a CT scan of her abdomen which showed a probable 8×5×8 cm left-sided adrenal mass. Functional tests for hormone excess were negative. She was referred to a tertiary referral centre and given the size of the adrenal mass; she consented for laparoscopic left adrenalectomy. During the operation, the mass was grossly adherent to the celiac axis, left renal pedicle and DJ flexure. A small nodule posterior to the renal vein was also identified. The operation was completed laparoscopically and she made an uneventful recovery. The specimen was reported as a poorly differentiated neuroblastoma. She had a postoperative MIBG scan which was negative for residual or metastatic disease. She was commenced on platinum-based chemotherapy with a plan for further radiological follow-up.

Extra-Adrenal Adult Neuroblastoma With Aberrant Germ Cell Marker Expression: Maturation After Chemotherapy as an Important Clue to a Challenging Diagnosis

Adult neuroblastoma is an extremely infrequent neoplasm, usually occurring in the adrenal medulla or in the paraspinal sympathetic ganglia, as its childhood counterpart. We report a very unusual case of a Schwannian stroma-poor adult neuroblastoma of inguinal location, showing aberrant expression of germ cell markers: SALL4 and OCT4. This aberrant marker expression, the unusual positivity for NKX2.2 and the very scattered (instead of diffuse strong) PHOX2B expression, complicated the initial diagnosis. In this case, the posttreatment histological evaluation revealed the neuroblastic nature of the lesion. Neuroblastoma maturation after treatment is an unusual finding in adults, and in this case, added an important clue for the final diagnosis. Germs cells markers expression in neuroblastoma is an interesting feature to explore and may define a subset of neuroblastomas with a different biological nature.

Treatment and outcome of adult-onset neuroblastoma

Adult-onset neuroblastoma is rare and little is known about its biology and clinical course. There is no established therapy for adult-onset neuroblastoma. Anti-GD2 immunotherapy is now standard therapy in children with high-risk neuroblastoma; however, its use has not been reported in adults. Forty-four adults (18-71 years old) diagnosed with neuroblastoma between 1979 and 2015 were treated at Memorial Sloan Kettering Cancer Center. Five, 1, 5 and 33 patients had INSS stage 1, 2, 3 and 4 diseases, respectively. Genetic abnormalities included somatic ATRX (58%) and ALK mutations (42%) but not MYCN-amplification. In the 11 patients with locoregional disease, 10-year progression-free (PFS) and overall survival (OS) was 35.4 ± 16.1% and 61.4 ± 15.3%, respectively. Among 33 adults with stage 4 neuroblastoma, 7 (21%) achieved complete response (CR) after induction chemotherapy and/or surgery. Seven patients with primary refractory neuroblastoma (all with osteomedullary but no soft tissue disease) received anti-GD2 antibodies, mouse or humanized 3F8. Antibody-related adverse events were similar to those in children, response rate being 71.4%. In patients with stage 4 disease at diagnosis, 5-year PFS was 9.7± 5.3% and most patients who were alive with disease at 5 years died of neuroblastoma over the next 5 years, 10-year OS being only 19.0 ± 8.2%. Patients who achieved CR after induction had superior PFS and OS (p = 0.006, p = 0.031, respectively). Adult-onset neuroblastoma appeared to have different biology from pediatric or adolescent NB, and poorer outcome. Complete disease control appeared to improve long-term survival. Anti-GD2 immunotherapy was well tolerated and might be beneficial.

TERT-mediated and ATRX-mediated Telomere Maintenance and Neuroblastoma

Neuroblastomas (NB) are one of the most common extracranial solid tumors in children, and they frequently display high heterogeneity in the disease course. With ongoing research, more information regarding the genetic etiology and molecular mechanisms underlying these contrasting phenotypes is being uncovered. The proto-oncogene MYCN is amplified in approximately 20% of NB cases and is considered a indicator of poor prognosis and an indicator of high-risk NB. The poor prognosis of high risk NB is incompletely explained by MYCN amplification. Recently, massive parallel sequencing studies reported several relatively common gene alterations, such as ATRX mutation and TERT rearrangement that are involved in telomere maintenance through telomerase activity and alternative lengthening of telomeres. Thus, these are important for understanding the etiology and molecular pathogenesis of NB, and hence, for identifying diagnostic and treatment markers. Development of telomerase inhibitors and identification of alternative lengthening of telomeres related targets will contribute to the individualized treatment for high-risk NB. In this mini-review, we will discuss the research progress of TERT-mediated and ATRX-mediated telomere maintenance and NB, especially high-risk tumors.

MYCN Amplification Is Associated with Repressed Cellular Immunity in Neuroblastoma: An In Silico Immunological Analysis of TARGET Database

Purpose

RNA and DNA sequencing data are traditionally used to discern intrinsic cellular pathways in cancer pathogenesis, their utility for investigating the tumor microenvironment (TME) has not been fully explored. This study explores the use of sequencing data to investigate immunity within the TME.

Experimental design

Here, we use immune cell fraction estimation analysis to determine the immune profiles in the microenvironment of neuroblastoma (NB) based on RNA-seq data in the TARGET database. The correlation between immune cell transcripts and prognosis in pediatric NB is also investigated.

Results

In silico analysis revealed a strong inverse correlation between MYCN amplification and leukocyte infiltration. This finding was validated by immunohistochemistry analysis in tumor samples. Moreover, the abundance of CD4 T cells strongly associated with better patient survival regardless of MYCN gene amplification, while those of CD8 T cells, NK or B cells do not. Based on characteristic cytokine expression of CD4 subsets in tumors, the Th2 rather than Th1 levels were associated with better prognosis.

Conclusion

We found that the in silico analysis of TARGET database reflected tumor immunity and was validated by the immunohistochemical tumor data. Our results reveal the association of MYCN amplification with repressed cellular immunity and the potential prognostic value of infiltrating CD4 T cell transcripts in pediatric NB. This analysis illustrates the potential role of MYCN in NB as a regulator of immune privilege and characterizes the power of in silico analysis for delineating cancer immunology and risk stratification.

Genetic abnormalities in adolescents and young adults with neuroblastoma: A report from the Italian Neuroblastoma group

BACKGROUND

Less than 5% of neuroblastomas (NB) occur in adolescents and young adults (AYA), in whom the disease has an indolent and fatal course.

PROCEDURE

We studied the genomic profile and histological characteristics of 34 NBs from AYA patients enrolled in the Italian Neuroblastoma Registry (INBR) between 1979 and 2009.

RESULTS

Disease was disseminated in 20 patients and localized in 14; 30/34 tumors were classified as NB and 4/34 as nodular ganglioneuroblastoma (nGNB). Segmental Chromosome Aberrations (SCAs) were observed in 29 tumors (85%) namely 1p imbalance (58%), 17q gain (52%), 9p loss (32%), 11q loss (30%), 1q gain (17%), 7q gain (17%), 2p gain (14%), 3p loss (14%), and 4p loss (7%). MYCN amplification and MYCN gain were detected in 3 (10%) and 2 cases (7%) respectively. An anaplastic lymphoma receptor tyrosine kinase (ALK) gene mutation study on the available cases from this cohort revealed 4/25 (16%) mutated cases. In parallel, alpha thalassaemia/mental retardation syndrome X linked (ATRX) gene mutations were also sought, a novel mutation being detected in 1/21 (4,7%) cases.

CONCLUSION

This study confirmed the low incidence of MYCN amplification in AYA and recorded a high frequency of 17q gain and 9p and 11q loss independently from the stage of the disease. The presence of 1q gain, which identifies patients with particularly aggressive disease, relapse and poor survival, was also detected. Furthermore, the frequency of ALK mutations suggests that a target-based therapy with ALK inhibitors might be effective in this subset of patients.