Neuroblastoma Metastasis Research Articles

NDPKA is not just a metastasis suppressor – be aware of its metastasis-promoting role in neuroblastoma

NDPK-A, encoded by nm23-H1 (also known as NME1) was the first metastasis suppressor discovered. Much of the attention has been focused on the metastasis-suppressing role of NDPK-A in human tumors, including breast carcinoma and melanoma. However, compelling evidence points to a metastasis-promoting role of NDPK-A in certain tumors such as neuroblastoma and lymphoma. To balance attention on this contrariety of NDPK-A in different cancer types, this review addresses the metastasis-promoting role of NDPK-A in neuroblastoma. Neuroblastoma is an embryonic tumor, arising from neural crest cells that fail to differentiate into the sympathetic nervous system. We summarize and discuss nm23-H1 genetics and the prognosis of neuroblastoma, structural and functional changes associated with the S120G mutation of NDPK-A, as well as the evidence supporting the role of NDPK-A as a metastasis promoter. Also discussed are the NDPK-A relevant molecular determinants of neuroblastoma metastasis, and metastasis-relevant neural crest development. Because of NDPK-A's dichotomous role in tumor metastasis as both a suppressor and a promoter, tumor genome/exome profiles are necessary to identify the molecular drivers of metastasis in the NDPK-A network for developing tumor-specific therapies.

Magnetic Resonance Imaging for Characterization of a Chick Embryo Model of Cancer Cell Metastases.

Metastasis is the most common cause of death for patients with cancer. To fully understand the steps involved in metastatic dissemination, in vivo models are required, of which murine ones are the most common. Therefore, preclinical imaging methods such as magnetic resonance imaging (MRI) have mainly been developed for small mammals and their potential to monitor cancer growth and metastasis in nonmammalian models is not fully harnessed. We have here used MRI to measure primary neuroblastoma tumor size and metastasis in a chick embryo model. We compared its sensitivity and accuracy to end-point fluorescence detection upon dissection. Human neuroblastoma cells labeled with green fluorescent protein (GFP) and micron-sized iron particles were implanted on the extraembryonic chorioallantoic membrane of the chick at E7. T2 RARE, T2-weighted fast low angle shot (FLASH) as well as time-of-flight MR angiography imaging were applied at E14. Micron-sized iron particle labeling of neuroblastoma cells allowed in ovo observation of the primary tumor and tumor volume measurement noninvasively. Moreover, T2 weighted and FLASH imaging permitted the detection of small metastatic deposits in the chick embryo, thereby reinforcing the potential of this convenient, 3R compliant, in vivo model for cancer research.

Microenvironment-Driven Shift of Cohesion/Detachment Balance within Tumors Induces a Switch toward Metastasis in Neuroblastoma

Neuroblastoma (NB) is a childhood cancer arising from sympatho-adrenal neural crest cells. Disseminated forms have high frequency of multiple tumoral foci whose etiology remains unknown; NB embryonic origin limits investigations in patients and current models. We developed an avian embryonic model driving human NB tumorigenesis in tissues homologous to patients. We found that aggressive NBs display a metastatic mode, secondary dissemination via peripheral nerves and aorta. Through tumor transcriptional profiling, we found that NB dissemination is induced by the shutdown of a pro-cohesion autocrine signal, SEMA3C, which constrains the tumoral mass. Lowering SEMA3C levels shifts the balance toward detachment, triggering NB cells to collectively evade the tumor. Together with patient cohort analysis, this identifies a microenvironment-driven pro-metastatic switch for NB.

Neuroblastoma Metastases: Leveraging the Avian Neural Crest

Neuroblastoma, an embryonal cancer of neural crest origin, shows metastases frequently at diagnosis. In this issue of Cancer Cell, Delloye-Bourgeois and colleagues demonstrate that neuroblastoma cell lines and patient-derived xenografts engraft and adopt a metastatic program in chick embryos. They identify Sema3C as a candidate switch that regulates metastatic spread.

LMO1 Synergizes with MYCN to Promote Neuroblastoma Initiation and Metastasis

A genome-wide association study identified LMO1, which encodes an LIM-domain-only transcriptional cofactor, as a neuroblastoma susceptibility gene that functions as an oncogene in high-risk neuroblastoma. Here we show that dβh promoter-mediated expression of LMO1 in zebrafish synergizes with MYCN to increase the proliferation of hyperplastic sympathoadrenal precursor cells, leading to a reduced latency and increased penetrance of neuroblastomagenesis. The transgenic expression of LMO1 also promoted hematogenous dissemination and distant metastasis, which was linked to neuroblastoma cell invasion and migration, and elevated expression levels of genes affecting tumor cell-extracellular matrix interaction, including loxl3, itga2b, itga3, and itga5. Our results provide invivo validation of LMO1 as an important oncogene that promotes neuroblastoma initiation, progression, and widespread metastatic dissemination.

Isatin inhibits SH-SY5Y neuroblastoma cell invasion and metastasis through MAO/HIF-1α/CXCR4 signaling.

Isatin was reported to possess anticancer activities through its effect on tumor proliferation, apoptosis, and metastasis in vitro and in vivo. This study aimed to elucidate the underlying mechanism behind isatin's ability to inhibit neuroblastoma cell metastasis. Our results demonstrated that isatin could inhibit neuroblastoma cell proliferation, invasion, and migration in a dose-dependent manner. Moreover, isatin inhibited the expression level of monoamine oxidase A as well as that of its downstream protein hypoxia-inducible factor 1α. Further study indicated that isatin inhibited reactive oxygen species production, extracellular signal-regulated kinase activation, vascular endothelial growth factor receptor-1 phosphorylation, and chemokine receptor type 4 expression. All results support the potential antimetastatic effect of isatin in neuroblatoma cells.

Abstract 4781: Epigenetic regulation of neuroblastoma tumorigenicity through MLL1 and JMJD3 modulation in cancer stem cells

Abstract Introduction: Increasing evidence suggest that epigenetic regulators play a critical role in cancer cell heterogeneity and in maintaining tumor sub-populations with enhanced tumor-initiating and drug-resistant capacities. Recently, we discovered a drug-resistant, highly tumorigenic, self-renewing cell sub-population with features of cancer stem cells (CSCs) in pediatric neuroblastoma (NB). This sub-population, characterized by surface expression of G-CSF receptor (CD114), can escape initial therapy and cause refractory and aggressively invasive relapsed disease. Recently, we found that the CSF3R gene that code for CD114 is expressed specifically in CD114+ sub-population (<1% of total cells) but not in CD114- bulk tumor cells. We hypothesize that this differential gene expression is epigenetically regulated and maintain heterogeneous NB sub-populations. Methods: Chromatin immunoprecipitation (ChIP)-qPCR for the histone marks H3K4me3 and H3K27me3 was performed in sorted NB sub-populations. Pathway qPCR arrays and orthotopic xenografts mouse model were used to determine the effects of epigenetic inhibitors in vitro and in vivo. Results: We found that the epigenetic regulators mixed-lineage leukemia-1 (MLL1; KMT2A; a H3K4me3 methyltransferase) and Jumonji D3 (JMJD3; KDM6B; a H3K27me3 demethylase) are overexpressed in CD114+ NB cells. These regulators maintain a reversible epigenetic switch of high H3K4me3 and low H3K27me3 histone marks at the CSF3R locus in CD114+ cells for active transcription. Targeting these epigenetic regulators with specific small-molecule inhibitors MM-102 (inhibit MLL1) and GSK-J4 (inhibit JMJD3) in NB, reverses the histone patterns at CSF3R promoter locus and block gene expression, induces apoptosis selectively in CD114+ cells, and inhibits overall NB proliferation in vitro. These inhibitors also inhibit the expression of cancer stem cell specific genes as determined by pathway arrays. Inhibiting MLL1 and JMJD3 in NB orthotopic xenografts significantly decreases tumor size (p<0.001) and metastatic burden (p<0.001) compared to controls. As expected, reduction in tumor size was significantly correlated with the reduction in tumor CD114+ cells. We also found that MM-102 and GSK-J4 sensitize NB tumors to genotoxic chemotherapy etoposide and further reduce tumor growth (p<0.01) in comparison to either drug alone. Interestingly, we do not observe any metastatic incidences in mice treated with MM-102+etoposide. Conclusion: Overall, we demonstrate that epigenetic regulators MLL1 and JMJD3 regulate the expression of critical genes and maintain NB CSC sub-population. Targeting these epigenetic regulators reduce NB tumorigenicity, metastasis and increase drug sensitivity. Further developing these strategies will pave the way for incorporating epigenetic inhibitors in current therapies for effectivity improving long-term cure rates. Citation Format: Saurabh Agarwal, Zaowen Chen, Julie A. Tomolonis, Sanjeev A. Vasudevan, Jason M. Shohet. Epigenetic regulation of neuroblastoma tumorigenicity through MLL1 and JMJD3 modulation in cancer stem cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4781. doi:10.1158/1538-7445.AM2017-4781

CFC1 is a cancer stemness-regulating factor in neuroblastoma.

BackgroundDespite the use of aggressive therapy, survival rates among high-risk neuroblastoma (NB) patients remain poor. Cancer stem cells (CSCs) are considered to be critically involved in the recurrence and metastasis of NB and are isolated as NB spheres.MethodsThe gene expression profiling of adherent (control) and sphere-forming primary NB cells was conducted using a gene expression microarray. CFC1, which functions in the development of embryos and decides the left-right axis, was strongly expressed in sphere-forming cells only and was related to the unfavorable prognosis of NB patients. The knockdown and overexpression of CFC1 were performed using a lentiviral system in NB cell lines. Sphere formation, cell proliferation, colony formation in soft agar, and xenograft tumor formation were analyzed.ResultsThe overexpression of CFC1 increased sphere formation, cell growth, and colony formation. These phenotypes, particularly sphere formation, and xenograft tumor formation were significantly suppressed by the knockdown of CFC1. CFC1 inhibited Activin A-induced NB cell differentiation and Smad2 phosphorylation in NB cell lines, indicating its involvement in tumorigenesis related to EGF-CFC co-receptor family molecule pathways. Collectively, these results indicate that CFC1 is a candidate molecule for the development of CSC-targeted therapy for NB.

Neuroblastoma metastatic to the central nervous system: Survival analyses from the German Childhood Cancer Registry and the literature.

10555 Background: Therapeutic innovation has resulted in an overall decline in childhood neuroblastoma (NB) mortality; however, metastatic NB to the central nervous system (CNS NB), which has emerged as a sanctuary site for NB metastases, remains difficult to treat and is typically fatal. The objective of this study was to describe the natural course of CNS NB. Methods: Data were sourced from a custom query of the German Childhood Cancer Registry (GCCR) and from the literature. Survival statistics were prepared from a diverse, thus generalizable, pool of CNS NB patients. Data are presented as secondary event-free and overall survival (EFS and OS) after diagnosis of first CNS recurrence from initial high-risk NB. Results: The GCCR query identified 85 patients with CNS NB diagnosed from 1990–2010, including 57 with isolated CNS disease. The median (95% confidence) EFS and OS times were 2.6 (1.5–3.8) and 4.7 (2.1–7.2) months, respectively, for all CNS NB patients, and 2.8 (1.4–4.1) and 6.8 (2.1–11.5) months, respectively, for isolated CNS NB patients. Secondary OS at 12, 18, and 36 months was 29.4%, 18.8%, and 8.2%, respectively, for all CNS NB patients, and 35.1%, 22.8%, and 12.3%, respectively, for isolated CNS NB patients. Thirteen publications were selected with 83 patients treated from 1979–2013. In addition to an inclusive analysis, a restricted analysis was performed, excluding patients who did not receive therapy with curative intent, to assess survival after therapeutic intervention. Median OS (95% confidence) was 5.6 (3.0–8.0) and 8.7 (5.8–11.0) months in the inclusive and restricted analyses, respectively. The proportion of patients surviving 12, 18, and 36 months at reporting were 24%, 12%, and 3.6%, respectively, for the inclusive population, and 33%, 17%, and 5%, respectively, for the restricted population. Conclusions: An assessment of the natural course of CNS NB from two sources arrived at similar conclusions with respect to overall and long-term survival. In general, median secondary OS is < 6 months and < 10% of patients survive 36 months. The findings were consistent across geographic regions and have not changed appreciably in 4 decades.

Highlights from Recent Cancer Literature

Highlights from Recent Cancer Literature

MYCN amplification predicts poor prognosis based on interphase fluorescence in situ hybridization analysis of bone marrow cells in bone marrow metastases of neuroblastoma

BackgroundMYCN gene amplification is related to risk stratification. Therefore it is important to identify accurately the level of the MYCN gene as early as possible in neuroblastoma (NB); however, for patients with bone marrow (BM) metastasis who need chemotherapy before surgery, timely detection of the MYCN gene is not possible due to the unavailability of primary tumors.MethodsMYCN gene status was evaluated in 81 BM metastases of NB by interphase fluorescence in situ hybridization (FISH) analysis of BM cells. The clinicobiological characteristics and prognostic impact of MYCN amplification in NB metastatic to BM were analyzed.ResultsMYCN amplification was found in 16% of patients with metastases, and the results were consistent with the primary tumors detected by pathological tissue FISH. MYCN amplification was associated with age, lactate dehydrogenase (LDH) levels and prognosis (P = 0.038, P < 0.001, P = 0.026). Clinical outcome was poorer in patients with MYCN amplification than in those without amplification (3-year EFS 28.8 ± 13.1 vs. 69.7 ± 5.7%, P = 0.005; 3-year OS 41.5 ± 14.7 vs. 76.7 ± 5.5%, P = 0.005).ConclusionsMYCN amplification predicts a poor outcome in NB metastatic to BM, and interphase FISH of bone marrow cells provides a timely direct and valid method to evaluate the MYCN gene status.

Unusual Indications for a Liver Transplant: A Single-Center Experience.

This study sought to evaluate the efficacy of liver transplant for unusual liver diseases. The results of 476 patients who underwent liver transplant from 1988 to January 2015 were retrospectively analyzed. Two hundred forty-five of them were adult patients and 231 of them were pediatric. Thirty-one patients had unusual liver disease. Of the 31 patients with unusual liver disease, 9 (29%) were adult and 22 (71%) were pediatric patients. In the pediatric group, indications for liver transplant were Alagille syndrome (n = 5), Crigler-Najjar syndrome type 1 (n = 5), glycogen storage disease (n = 3), oxalosis (n = 3), familial hypercholesterolemia (n = 2), alpha-1-antitrypsin deficiency (n = 2), Caroli disease (n = 1), and cystic neuroblastoma metastasis (n = 1). Six patients (27.2%) had acute rejection episodes and were successfully treated with pulse steroids. In 2 patients, retransplant was performed for chronic rejection. Three patients died during follow-up (13.6%): 2 because of sepsis and 1 because of cranial hemorrhage. In the adult group, indications for liver transplant were neuroendocrine tumor metastasis (n = 1), liver angiosarcoma (n = 1), familial hypercholesterolemia (n = 2), alveolar hydatid disease (n = 2), cystic fibrosis (n = 1), congenital hepatic fibrosis (n = 1), and oxalosis (n = 1). Four patients (44.4%) had acute rejection episodes and were successfully treated with pulse steroid therapy. One patient died due to the recurrence of primary disease (liver angiosarcoma) during follow-up (11.1%). Advances in liver transplant and our understanding about unusual liver disease have led to significant improvements in managing these diseases. Liver transplant effectively treats the underlying defect and the complications of portal hypertension, or risk of malignancy for those disorders, in which the liver is affected.

A Metastatic Mouse Model Identifies Genes That Regulate Neuroblastoma Metastasis.

Metastatic relapse is the major cause of death in pediatric neuroblastoma, where there remains a lack of therapies to target this stage of disease. To understand the molecular mechanisms mediating neuroblastoma metastasis, we developed a mouse model using intracardiac injection and in vivo selection to isolate malignant cell subpopulations with a higher propensity for metastasis to bone and the central nervous system. Gene expression profiling revealed primary and metastatic cells as two distinct cell populations defined by differential expression of 412 genes and of multiple pathways, including CADM1, SPHK1, and YAP/TAZ, whose expression independently predicted survival. In the metastatic subpopulations, a gene signature was defined (MET-75) that predicted survival of neuroblastoma patients with metastatic disease. Mechanistic investigations demonstrated causal roles for CADM1, SPHK1, and YAP/TAZ in mediating metastatic phenotypes in vitro and in vivo Notably, pharmacologic targeting of SPHK1 or YAP/TAZ was sufficient to inhibit neuroblastoma metastasis in vivo Overall, we identify gene expression signatures and candidate therapeutics that could improve the treatment of metastatic neuroblastoma. Cancer Res; 77(3); 696-706. ©2017 AACR.

ARID1A gene knockdown promotes neuroblastoma migration and invasion

Neuroblastoma is the most common extracranial solid tumor in childhood which often acquires drug resistance and becomes aggressive phenotypes. The high-risk patients suffer from high mortality due to the limitation of the treatment strategies. ARID1A (AT-rich interactive domain-containing protein 1A), a subunit of SWI/SNF complexes, is considered as a tumor suppressor in many cancers. The aim of the present study was to investigate the effect of ARID1A on migration and invasion in neuroblastoma cells. The shRNA targeting ARID1A was designed and delivered into SK-N-SH cells to knock down ARID1A expression. Knockdown of ARID1A by shRNA significantly increased the viability and invasion ability, and caused G1 arrest inhibition and DNA synthesis increase in SK-N-SH cells. Moreover, Knockdown of ARID1A increased the activity and expression of matrix metalloproteinase (MMP)-2 and -9 in SK-N-SH cells. Furthermore, ARID1A knockdown caused diminished expression of E-cadherin, enhanced expression of N-cadherin and β-catenin nuclear translocation in SK-N-SH cells. These results suggest that loss of ARID1A may associate with the promotion of invasion and metastasis of neuroblastoma. Our findings indicate ARID1A is a tumor suppressor in neuroblastoma.

An Endocrine Picture In Disguise: A Progressive Olfactory Neuroblastoma Complicated With Ectopic Cushing Syndrome

ABSTRACT Objective: To describe a unique case of a 61-year-old patient presenting with ectopic Cushing syndrome as a paraneoplastic phenomenon due to adrenocorticotropic hormone (ACTH)-secreting bone metastasis of an olfactory neuroblastoma (ON). Methods: We report a detailed case, with clinical, biochemical, and imaging findings and compare it with existing literature. Results: A patient with an ON, with subsequent 10-year stable disease after initial craniofacial surgery, presented with paraparesis due to progressively metastasized ON disease located in the thoracic spine. During palliative chemotherapy, severe hypokalemia and muscle weakness developed, being part of paraneoplastic Cushing syndrome. Examination showed that metastatic bone lesions were mostly responsible for the ectopic secretion of ACTH, with just a few ACTH-secreting tumor cells located in the primary tumor. She was treated with a combination of ketoconazole and metyrapone that controlled cortisol levels. However, low potassium levels ...

PI3K and MAPK pathways mediate the BDNF/TrkB-increased metastasis in neuroblastoma.

Brain-derived neurotrophic factor (BDNF) and its tyrosine kinase receptor TrkB have been reported to be associated with poor prognosis in neuroblastoma (NB) patients. Our previous studies indicated that BDNF activation of TrkB induces chemo-resistance through activation of phosphoinositide-3-kinase (PI3K)/Akt pathway. In this study, we investigated the role of BDNF/TrkB on metastasis in NB. A tetracycline-regulated TrkB-expressing NB cell line (TB3) was used. Scratch wound healing assay, Boyden chamber migration, and invasion assays were performed to study the migration and invasion of TB3 cells. A tumor xenograft model using SCID-Beige mice was utilized to detect the metastasis of NB tumors in vivo. Inhibitors of PI3K, MAPK, Akt, and mTOR were used. Western blotting was performed to study the expressions of P-Akt, P-Erk, and P-mTOR. Our results showed that in TrkB-expressing NB cells, BDNF treatment significantly increased gap closing (P < 0.01) in scratch wound healing assay, also significantly enhanced the numbers of migrating cells (P < 0.01) and invading cells (P < 0.01) in the Boyden chamber migration and invasion assays. In vivo, NB distant metastases were significantly increased in mice with TrkB-expressing xenograft tumors compared to those with non-TrkB-expressing tumors (P < 0.05). Pre-treatment with any of the inhibitors for PI3K (LY294002), MAPK (PD98059), Akt (perifosine), or mTOR (rapamycin) blocked the BDNF/TrkB-induced increases of cell migration and invasion in TB3 cells, and also blocked the BDNF/TrkB-induced expressions of P-Akt, P-Erk, and P-mTOR. These data indicated that BDNF/TrkB increased metastasis in NB via PI3K/Akt/mTOR and MAPK pathways, and BDNF/TrkB and the downstream targets may be potential targets for the treatment of NB metastasis.Electronic supplementary materialThe online version of this article (doi:10.1007/s13277-016-5433-z) contains supplementary material, which is available to authorized users.

MYCN and HDAC5 transcriptionally repress CD9 to trigger invasion and metastasis in neuroblastoma.

The systemic and resistant nature of metastatic neuroblastoma renders it largely incurable with current multimodal treatment. Clinical progression stems mainly from the increasing burden of metastatic colonization. Therapeutically inhibiting the migration-invasion-metastasis cascade would be of great benefit, but the mechanisms driving this cycle are as yet poorly understood. In-depth transcriptome analyses and ChIP-qPCR identified the cell surface glycoprotein, CD9, as a major downstream player and direct target of the recently described GRHL1 tumor suppressor. CD9 is known to block or facilitate cancer cell motility and metastasis dependent upon entity. High-level CD9 expression in primary neuroblastomas correlated with patient survival and established markers for favorable disease. Low-level CD9 expression was an independent risk factor for adverse outcome. MYCN and HDAC5 colocalized to the CD9 promoter and repressed transcription. CD9 expression diminished with progressive tumor development in the TH-MYCN transgenic mouse model for neuroblastoma, and CD9 expression in neuroblastic tumors was far below that in ganglia from wildtype mice. Primary neuroblastomas lacking MYCN amplifications displayed differential CD9 promoter methylation in methyl-CpG-binding domain sequencing analyses, and high-level methylation was associated with advanced stage disease, supporting epigenetic regulation. Inducing CD9 expression in a SH-EP cell model inhibited migration and invasion in Boyden chamber assays. Enforced CD9 expression in neuroblastoma cells transplanted onto chicken chorioallantoic membranes strongly reduced metastasis to embryonic bone marrow. Combined treatment of neuroblastoma cells with HDAC/DNA methyltransferase inhibitors synergistically induced CD9 expression despite hypoxic, metabolic or cytotoxic stress. Our results show CD9 is a critical and indirectly druggable suppressor of the invasion-metastasis cycle in neuroblastoma.

Proptosis in a previously well five-year-old boy

Neuroblastoma metastasis. Ophthalmic findings may be the first presentation of a neuroblastoma which is the commonest paediatric tumour to metastasise to the orbit. The primary tumour is usually intraabdominal. Approximately 10–20% of children will have orbital metastases [1Ahmed S. Goel S. Khandwala M. et al.Neuroblastoma with orbital metastasis: ophthalmic presentation and role of the ophthalmologists.Eye. 2006; 20: 466-470Crossref PubMed Scopus (36) Google Scholar, 2Dubois S.G. Kalka Y. Lukens J.N. et al.Metastatic sites in stage IV and IVS neuroblastoma correlate with age, tumour biology, and survival.J Pediatr Hematol Oncol. 1999; 21: 181-189Crossref PubMed Scopus (308) Google Scholar] and up to 50% are bilateral [3Chung E.M. Murphey M.D. Specht C.S. et al.Pediatric orbit tumours and tumour like lesions: osseous lesions of the orbit.Radiographics. 2008; 28: 1193-1214Crossref PubMed Scopus (54) Google Scholar, 4Alfano J.E. Ophthalmological aspects of neuroblastomatosis: a study of 53 verified cases.Trans Am Acad Ophthalmol Otolaryngol. 1968; 72: 830-848PubMed Google Scholar, 5Altonbary Y. Mansour A.K. Sarhan M. et al.Proptosis is a pediatric dilemma.Ann Pediatr Child Health. 2015; 3: 1066Google Scholar]. Proptosis and ecchymosis (“raccoon eyes”) are the commonest ocular manifestations [[3]Chung E.M. Murphey M.D. Specht C.S. et al.Pediatric orbit tumours and tumour like lesions: osseous lesions of the orbit.Radiographics. 2008; 28: 1193-1214Crossref PubMed Scopus (54) Google Scholar]. The most common cause of proptosis in a child is orbital cellulitis [[5]Altonbary Y. Mansour A.K. Sarhan M. et al.Proptosis is a pediatric dilemma.Ann Pediatr Child Health. 2015; 3: 1066Google Scholar]. Histiocytosis, haemangioma or lymphangioma are further benign causes. Malignant aetiologies include rhabdomyosarcoma, Ewing’s sarcoma, lymphoma and metastases from a neuroblastoma, bone tumours or leukaemia [[5]Altonbary Y. Mansour A.K. Sarhan M. et al.Proptosis is a pediatric dilemma.Ann Pediatr Child Health. 2015; 3: 1066Google Scholar]. Typical CT or MRI features are an extra-conal soft tissue mass arising from the wall of the orbit [[8]Lonergan G.J. Schwab C.M. Suarex E.S. et al.Neuroblastoma, ganglioneuroblastoma, and ganglioneuroma: Radiologic-Pathologic Correlation.Radiographics. 2002; 22: 911-934Crossref PubMed Scopus (478) Google Scholar]. As in this patient, it can be locally aggressive extending into the infratemporal fossa structures or intra-cranially, with bony destruction of the roof and wall of the orbit and resultant bony spiculation [3Chung E.M. Murphey M.D. Specht C.S. et al.Pediatric orbit tumours and tumour like lesions: osseous lesions of the orbit.Radiographics. 2008; 28: 1193-1214Crossref PubMed Scopus (54) Google Scholar, 6Wells R.G. Sty J.R. Gonnering R.S. Imaging of the pediatric eye and orbit.Radiographics. 1989; 9: 1023-1044Crossref PubMed Scopus (14) Google Scholar, 7Lallemand D.P. Brasch R.C. Char D.H. et al.Orbital tumours in children: characterisation by computed tomography.Radiology. 1984; 151: 85-88Crossref PubMed Scopus (8) Google Scholar]. The mass may be unilateral or bilateral, unlike a rhabdomyosarcoma which is typically unilateral [[3]Chung E.M. Murphey M.D. Specht C.S. et al.Pediatric orbit tumours and tumour like lesions: osseous lesions of the orbit.Radiographics. 2008; 28: 1193-1214Crossref PubMed Scopus (54) Google Scholar]. Furthermore, rhabdomyosarcoma may involve anterior pre-septal orbital structures but a neuroblastoma will usually not [[3]Chung E.M. Murphey M.D. Specht C.S. et al.Pediatric orbit tumours and tumour like lesions: osseous lesions of the orbit.Radiographics. 2008; 28: 1193-1214Crossref PubMed Scopus (54) Google Scholar]. Neuroblastomas can cause dural and leptomeningeal metastases, with involvement of the skull causing diastasis of affected sutures [3Chung E.M. Murphey M.D. Specht C.S. et al.Pediatric orbit tumours and tumour like lesions: osseous lesions of the orbit.Radiographics. 2008; 28: 1193-1214Crossref PubMed Scopus (54) Google Scholar, 8Lonergan G.J. Schwab C.M. Suarex E.S. et al.Neuroblastoma, ganglioneuroblastoma, and ganglioneuroma: Radiologic-Pathologic Correlation.Radiographics. 2002; 22: 911-934Crossref PubMed Scopus (478) Google Scholar]. This child had clinical, radiological and pathological findings consistent with metastatic neuroblastoma and an MRI abdomen (Fig. 2) revealed a left adrenal primary site. Proptosis in a previously well five-year-old boyJournal of Clinical NeuroscienceVol. 34PreviewA five-year-old boy presented with a one-week history of left-sided proptosis and retro orbital pain, with no prior medical or surgical history. On examination, there was left-sided proptosis with no visual field defect or other neurological abnormality. Full blood count, electrolytes and inflammatory markers were unremarkable. Full-Text PDF

Stathmin mediates neuroblastoma metastasis in a tubulin-independent manner via RhoA/ROCK signaling and enhanced transendothelial migration.

Neuroblastoma, the most common solid tumor of young children, frequently presents with aggressive metastatic disease and for these children the 5-year survival rates are dismal. Metastasis, the movement of cancer cells from one site to another, involves remodeling of the cytoskeleton including altered microtubule dynamics. The microtubule-destabilizing protein, stathmin, has recently been shown to mediate neuroblastoma metastasis although precise functions remain poorly defined. In this study we investigated stathmin's contribution to the metastatic process and potential mechanism(s) by which it exerts these effects. Stathmin suppression significantly reduced neuroblastoma cell invasion of 3D tumor spheroids into an extracellular matrix. Moreover, inhibiting stathmin expression significantly reduced transendothelial migration in two different neuroblastoma cell lines in vitro. Inhibition of ROCK, a key regulator of cell migration, in neuroblastoma cells highlighted that stathmin regulates transendothelial migration through ROCK signaling. Reduced stathmin expression in neuroblastoma cells significantly increased the activation of the RhoA small GTPase. Notably, re-expression of either wild type or a phospho-mimetic stathmin mutant (4E) made defective in tubulin binding returned cell migration and transendothelial migration back to control levels, indicating that stathmin may influence these processes in neuroblastoma cells independent of tubulin binding. Finally, stathmin suppression in neuroblastoma cells significantly reduced whole body, lung, kidney and liver metastases in an experimental metastases mouse model. In conclusion, stathmin suppression interferes with the metastatic process via RhoA/ROCK signaling in neuroblastoma cells. These findings highlight the importance of stathmin to the metastatic process and its potential as a therapeutic target for the treatment of neuroblastoma.

Musculocontractural Ehlers-Danlos syndrome and neurocristopathies: dermatan sulfate is required for Xenopus neural crest cells to migrate and adhere to fibronectin.

ABSTRACTOf all live births with congenital anomalies, approximately one-third exhibit deformities of the head and face. Most craniofacial disorders are associated with defects in a migratory stem and progenitor cell population, which is designated the neural crest (NC). Musculocontractural Ehlers–Danlos syndrome (MCEDS) is a heritable connective tissue disorder with distinct craniofacial features; this syndrome comprises multiple congenital malformations that are caused by dysfunction of dermatan sulfate (DS) biosynthetic enzymes, including DS epimerase-1 (DS-epi1; also known as DSE). Studies in mice have extended our understanding of DS-epi1 in connective tissue maintenance; however, its role in fetal development is not understood. We demonstrate that DS-epi1 is important for the generation of isolated iduronic acid residues in chondroitin sulfate (CS)/DS proteoglycans in early Xenopus embryos. The knockdown of DS-epi1 does not affect the formation of early NC progenitors; however, it impairs the correct activation of transcription factors involved in the epithelial–mesenchymal transition (EMT) and reduces the extent of NC cell migration, which leads to a decrease in NC-derived craniofacial skeleton, melanocytes and dorsal fin structures. Transplantation experiments demonstrate a tissue-autonomous role for DS-epi1 in cranial NC cell migration in vivo. Cranial NC explant and single-cell cultures indicate a requirement of DS-epi1 in cell adhesion, spreading and extension of polarized cell processes on fibronectin. Thus, our work indicates a functional link between DS and NC cell migration. We conclude that NC defects in the EMT and cell migration might account for the craniofacial anomalies and other congenital malformations in MCEDS, which might facilitate the diagnosis and development of therapies for this distressing condition. Moreover, the presented correlations between human DS-epi1 expression and gene sets of mesenchymal character, invasion and metastasis in neuroblastoma and malignant melanoma suggest an association between DS and NC-derived cancers.