Abstract A02: Neuroblastoma patient-derived orthotopic xenografts: Clinically relevant models for drug testing

Abstract Widespread metastasis is a major problem for the treatment of high-risk neuroblastoma. Relevant neuroblastoma animal models are hence needed to study and target high-risk metastatic neuroblastoma. We developed neuroblastoma patient-derived orthotopic xenografts (PDXs) using viably cryopreserved or fresh patient neuroblastoma fragments which were implanted orthotopically into immunodeficient NSG mice. Immunohistochemistry showed that PDXs retain neuroblastoma markers and a highly infiltrative growth pattern. Importantly, we found distant metastasis to lungs, liver and bone marrow. Single nucleotide polymorphism array analysis confirmed that PDXs maintain patient-specific chromosomal…

Extracellular matrix composition defines an ultra-high-risk group of neuroblastoma within the high-risk patient cohort

Background: Although survival for neuroblastoma patients has dramatically improved in recent years, a substantial number of children in the high-risk subgroup still die. Methods: We aimed to define a subgroup of ultra-high-risk patients from within the high-risk cohort. We used advanced morphometric approaches to quantify and characterise blood vessels, reticulin fibre networks, collagen type I bundles, elastic fibres and glycosaminoglycans in 102 high-risk neuroblastomas specimens. The Kaplan-Meier method was used to correlate the analysed elements with survival. Results: The organisation of blood vessels and reticulin fibres in neuroblastic tumours defined an ultra-high-risk patient subgr…

Gain of MYCN region in a Wilms tumor-derived xenotransplanted cell line.

Wilms tumor is one of the most common pediatric malignant tumors of the kidney. Although the WT1 gene, located at 11p13, has been proven to be implicated in the development of Wilms tumor, other genes such as MYCN are also involved. The purpose of this study is to genetically characterize a Wilms tumor metastasis xenotransplanted in nude mice. Immunogenotype evolution of the xenografts material was monitored for 29 months using molecular techniques, fluorescent in situ hybridization and multiplex ligation-dependent probe amplification, in addition to immunohistochemistry in tissue microarrays. Genetic alterations present in the original tumor and retained in the xenotransplanted tumor were …

Comparative genetic study of intratumoral heterogenous MYCN amplified neuroblastoma versus aggressive genetic profile neuroblastic tumors.

Intratumoral heterogeneous MYCN amplification (hetMNA) is an unusual event in neuroblastoma with unascertained biological and clinical implications. Diagnosis is based on the detection of MYCN amplification surrounded by non-amplified tumor cells by fluorescence in situ hybridization (FISH). To better define the genetic features of hetMNA tumors, we studied the Spanish cohort of neuroblastic tumors by FISH and single nucleotide polymorphism arrays. We compared hetMNA tumors with homogeneous MNA (homMNA) and nonMNA tumors with 11q deletion (nonMNA w11q-). Of 1091 primary tumors, 28 were hetMNA by FISH. Intratumoral heterogeneity of 1p, 2p, 11q and 17q was closely associated with hetMNA tumor…

TMA Vessel Segmentation Based on Color and Morphological Features: Application to Angiogenesis Research

Given that angiogenesis and lymphangiogenesis are strongly related to prognosis in neoplastic and other pathologies and that many methods exist that provide different results, we aim to construct a morphometric tool allowing us to measure different aspects of the shape and size of vascular vessels in a complete and accurate way. The developed tool presented is based on vessel closing which is an essential property to properly characterize the size and the shape of vascular and lymphatic vessels. The method is fast and accurate improving existing tools for angiogenesis analysis. The tool also improves the accuracy of vascular density measurements, since the set of endothelial cells forming a…

Neuroblastoma patient-derived orthotopic xenografts reflect the microenvironmental hallmarks of aggressive patient tumours.

AbstractTreatment of high-risk childhood neuroblastoma is a clinical challenge which has been hampered by a lack of reliable neuroblastoma mouse models for preclinical drug testing. We have previously established invasive and metastasising patient-derived orthotopic xenografts (PDXs) from high-risk neuroblastomas that retained the genotypes and phenotypes of patient tumours. Given the important role of the tumour microenvironment in tumour progression, metastasis, and treatment responses, here we analysed the tumour microenvironment of five neuroblastoma PDXs in detail. The PDXs resembled their parent tumours and retained important stromal hallmarks of aggressive lesions including rich bloo…

NeuPAT: an intranet database supporting translational research in neuroblastic tumors.

Translational research in oncology is directed mainly towards establishing a better risk stratification and searching for appropriate therapeutic targets. This research generates a tremendous amount of complex clinical and biological data needing speedy and effective management. The authors describe the design, implementation and early experiences of a computer-aided system for the integration and management of data for neuroblastoma patients. NeuPAT facilitates clinical and translational research, minimizes the workload in consolidating the information, reduces errors and increases correlation of data through extensive coding. This design can also be applied to other tumor types.

Abstract B23: Neuroblastoma patient-derived orthotopic xenografts: Clinically relevant models for drug testing

Abstract Background: We previously established neuroblastoma patient-derived orthotopic xenografts (PDXs) by implanting patient neuroblastoma fragments into immunodeficient NSG mice. SNP array analysis confirmed that PDXs maintain patient-specific chromosomal aberrations 1p del, MYCN amp and 17q gain. Immunohistochemistry showed that PDXs retain neuroblastoma markers and a highly infiltrative growth pattern. Importantly, we found spontaneous distant metastasis to lungs, liver and bone marrow. In vitro cultures established from the PDXs express neuroblastoma markers and retain their tumorigenic and metastatic ability in vivo after orthotopic injection. Methods and Results: Given the importan…

A stiff extracellular matrix is associated with malignancy in peripheral neuroblastic tumors

Purpose and objective Improved prognosis for patients with peripheral neuroblastic tumors (PNB) depends on enhanced pretreatment risk stratification combined with research into new therapeutic targets. This study investigated the potential contribution of extracellular matrix (ECM) elements toward this endeavor. Methods We characterized certain elements such as reticulin fibers, collagen type I fibers, and elastic fibers by digital pathology in almost 400 untreated PNB. Results A reticular and poorly porous ECM was identified in neuroblastomas (NBs) from patients with clinical and biological features associated with poor prognosis compared with a loose and permeable matrix found in NBs of t…

Neuroblastoma after Childhood: Prognostic Relevance of Segmental Chromosome Aberrations, ATRX Protein Status, and Immune Cell Infiltration

AbstractNeuroblastoma (NB) is a common malignancy in children but rarely occurs during adolescence or adulthood. This subgroup is characterized by an indolent disease course, almost uniformly fatal, yet little is known about the biologic characteristics. The aim of this study was to identify differential features regarding DNA copy number alterations, α-thalassemia/mental retardation syndrome X-linked (ATRX) protein expression, and the presence of tumor-associated inflammatory cells. Thirty-one NB patients older than 10 years who were included in the Spanish NB Registry were considered for the current study; seven young and middle-aged adult patients (range 18-60 years) formed part of the c…

Vascular patterns provide therapeutic targets in aggressive neuroblastic tumors

// Irene Tadeo 1 , Gloria Bueno 2 , Ana P. Berbegall 1 , M. Milagro Fernandez-Carrobles 2 , Victoria Castel 3 , Marcial Garcia-Rojo 4 , Samuel Navarro 1 , Rosa Noguera 1 1 Pathology Department, Medical School, University of Valencia, INCLIVA, 46010 Valencia, Spain 2 VISILAB, E.T.S. Ingenieros Industriales, University of Castilla-La Mancha, 13071 Ciudad Real, Spain 3 Pediatric Oncology Unit, University and Polytechnic Hospital La Fe, 46026 Valencia, Spain 4 Department of Pathology, Hospital de Jerez de la Frontera, 11407 Jerez de la Frontera, Cadiz, Spain Correspondence to: Rosa Noguera Salva, e-mail: rnoguera@uv.es Keywords: extracellular matrix, blood vessels, capillaries, sinusoids, neuro…

Genetic Instability and Intratumoral Heterogeneity in Neuroblastoma with MYCN Amplification Plus 11q Deletion

Background/Aim Genetic analysis in neuroblastoma has identified the profound influence of MYCN amplification and 11q deletion in patients’ prognosis. These two features of high-risk neuroblastoma usually occur as mutually exclusive genetic markers, although in rare cases both are present in the same tumor. The purpose of this study was to characterize the genetic profile of these uncommon neuroblastomas harboring both these high-risk features. Methods We selected 18 neuroblastomas with MNA plus 11q loss detected by FISH. Chromosomal aberrations were analyzed using Multiplex Ligation-dependent Probe Amplification and Single Nucleotide Polymorphism array techniques. Results and Conclusion Thi…

Anaplastic lymphoma kinase expression in neuroblastomas and its relationship with genetic, prognostic, and predictive factors

A morphometric tool applied to angiogenesis research based on vessel segmentation

Given that angiogenesis and lymphangiogenesis are strongly related to prognosis in neoplastic and other pathologies, and that some existing methods for their study provide different results, we aim to construct a morphometric tool to allow complete and accurate quantification and measurement of different aspects of the shape and size of vascular vessels.

Quantitative modeling of clinical, cellular, and extracellular matrix variables suggest prognostic indicators in cancer: a model in neuroblastoma

BACKGROUND: Risk classification and treatment stratification for cancer patients is restricted by our incomplete picture of the complex and unknown interactions between the patient's organism and tumor tissues (transformed cells supported by tumor stroma). Moreover, all clinical factors and laboratory studies used to indicate treatment effectiveness and outcomes are by their nature a simplification of the biological system of cancer, and cannot yet incorporate all possible prognostic indicators. METHODS: A multiparametric analysis on 184 tumor cylinders was performed. To highlight the benefit of integrating digitized medical imaging into this field, we present the results of computational s…