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

Abstract

Treatment 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 blood and lymphatic vascularisation, pericyte coverage, high numbers of cancer-associated fibroblasts, tumour-associated macrophages, and extracellular matrix components. Patient-derived tumour endothelial cells occasionally formed blood vessels in PDXs; however, tumour stroma was, overall, of murine origin. Lymphoid cells and lymphatic endothelial cells were found in athymic nude mice but not in NSG mice; thus, the choice of mouse strain dictates tumour microenvironmental components. The murine tumour microenvironment of orthotopic neuroblastoma PDXs reflects important hallmarks of aggressive and metastatic clinical neuroblastomas. Neuroblastoma PDXs are clinically relevant models for preclinical drug testing.

Evidence of Tumour Microenvironment and Stromal Cellular Components in Retinoblastoma

“…The role of TME, its associated cellular, non-cellular components have been well studied in detail in various types of adult-onset epithelial cancers [23,29] and some paediatric cancers such as neuroblastoma and medulloblastoma [17,36,37]. Contrarily, very few studies outline the existence of TME in RB [32][33][34][35].…”

Patient-Derived Xenograft Models Reveal Intratumor Heterogeneity and Temporal Stability in Neuroblastoma

“…Animal procedures were performed as described previously (13,14). Briefly, 4-to-6-week-old female or male NSG mice were housed under pathogen-free conditions and received autoclaved water and food.…”

“…Briefly, 4-to-6-week-old female or male NSG mice were housed under pathogen-free conditions and received autoclaved water and food. We have previously established neuroblastoma PDOXs through the implantation of undissociated patient tumor fragments into the paraadrenal space of immunodeficient NSG mice (13,14). Established PDOXs underwent serial orthotopic transplantation into next generation NSG mice to establish up to eight in vivo generations for each PDOX model.…”

“…We have previously established neuroblastoma patient-derived orthotopic xenografts (PDOX), which retain the histopathologic, stromal, and metastatic features of aggressive patient tumors (13,14). We prefer to use PDOXs instead of subcutaneous PDXs, because orthotopic tumors have more relevant biology (15) and retain spontaneous metastatic capacity (16).…”

Patient-Derived-Tumor-Xenograft: modeling cancer for basic and translational cancer research

“…For example, Breakeveldt N et al using neuroblastoma PDTX have reported that mice stroma recapitulate the clinical hallmarks of original primary neuroblastomas, such as the rich vascularization, macrophage infiltration, and CAF and ECM composition. Moreover, the authors observed that patientderived endothelial cells could form blood vessels, although tumor stroma was predominantly replaced with murine stroma [52]. On the same line, Sansone P et al have generated PDTX models of luminal breast cancer and isolated cancer-associated fibroblast from hormonal therapy resistant bone metastases.…”