Project description:Pediatric brain tumors are the leading cause of cancer-related death in children. Patient-derived orthotopic xenografts (PDOX) of childhood brain tumors have recently emerged as a biologically faithful vehicle for testing novel and more effective therapies. Herein, we provide the histopathological and molecular analysis of 37 novel PDOX models generated from pediatric brain tumor patients treated at St. Jude Children's Research Hospital. Using a combination of histopathology, whole-genome and whole-exome sequencing, RNA-sequencing, and DNA methylation arrays, we demonstrate the overall fidelity and inter-tumoral molecular heterogeneity of pediatric brain tumor PDOX models. These models represent frequent as well as rare childhood brain tumor entities, including medulloblastoma, ependymoma, atypical teratoid rhabdoid tumor, and embryonal tumor with multi-layer rosettes. PDOX models will be valuable platforms for evaluating novel therapies and conducting pre-clinical trials to accelerate progress in the treatment of brain tumors in children. All described PDOX models and associated datasets can be explored using an interactive web-based portal and will be made freely available to the research community upon request.
Project description:Primary patient pediatric brain tumors from patients treated at SJCRH were implanted and amplified only in the brain of immunocompromised mice without tissue culture steps and referred as patient-derived orthotopic xenografts (Smith et al, Acta Neuropathologica, 2020).
Project description:Pancreatic ductal adenocarcinomas (PDACs) overexpress pro-angiogenic factors but are not viewed as vascular. Using data from The Cancer Genome Atlas we demonstrate that a subset of PDACs exhibits a strong pro-angiogenic signature that includes 37 genes, such as HDAC9, that are overexpressed in PDAC arising in KRC mice, which express mutated Kras and lack RB. Moreover, patient-derived orthotopic xenografts can exhibit tumor angiogenesis, whereas conditioned media (CM) from KRC-derived pancreatic cancer cells (PCCs) enhance endothelial cell (EC) growth and migration, and activate canonical TGF-? signaling and STAT3. Inhibition of the type I TGF-? receptor with SB505124 does not alter endothelial activation in vitro, but decreases pro-angiogenic gene expression and suppresses angiogenesis in vivo. Conversely, STAT3 silencing or JAK1-2 inhibition with ruxolitinib blocks CM-enhanced EC proliferation. STAT3 disruption also suppresses endothelial HDAC9 and blocks CM-induced HDAC9 expression, whereas HDAC9 re-expression restores CM-enhanced endothelial proliferation. Moreover, ruxolitinib blocks mitogenic EC/PCC cross-talk, and suppresses endothelial p-STAT3 and HDAC9, and PDAC progression and angiogenesis in vivo, while markedly prolonging survival of KRC mice. Thus, targeting JAK1-2 with ruxolitinib blocks a final pathway that is common to multiple pro-angiogenic factors, suppresses EC-mediated PCC proliferation, and may be useful in PDACs with a strong pro-angiogenic signature.
Project description:Pediatric solid tumors arise from endodermal, ectodermal, or mesodermal lineages. Although the overall survival of children with solid tumors is 75%-80%, that of children with recurrent disease is below 30%. To capture the complexity and diversity of pediatric solid tumors and establish new models of recurrent disease, we developed a protocol to produce orthotopic patient-derived xenografts (O-PDXs) at diagnosis, recurrence, and autopsy. Tumor specimens were received from 168 patients, and 64 O-PDXs were established for 12 types of pediatric solid tumors. The origins of the O-PDX tumors were reflected in their gene-expression profiles and epigenomes. Genomic profiling of the tumors, including detailed clonal analysis, was performed to determine whether the clonal population in the xenograft recapitulated the patientÂ’s tumor. We identified several drug vulnerabilities and showed that the combination of a WEE1 inhibitor (AZD1775), irinotecan, and vincristine can lead to complete response in multiple rhabdomyosarcoma O-PDX tumors in vivo.
Project description:Paediatric solid tumours arise from endodermal, ectodermal, or mesodermal lineages. Although the overall survival of children with solid tumours is 75%, that of children with recurrent disease is below 30%. To capture the complexity and diversity of paediatric solid tumours and establish new models of recurrent disease, here we develop a protocol to produce orthotopic patient-derived xenografts at diagnosis, recurrence, and autopsy. Tumour specimens were received from 168 patients, and 67 orthotopic patient-derived xenografts were established for 12 types of cancer. The origins of the patient-derived xenograft tumours were reflected in their gene-expression profiles and epigenomes. Genomic profiling of the tumours, including detailed clonal analysis, was performed to determine whether the clonal population in the xenograft recapitulated the patient's tumour. We identified several drug vulnerabilities and showed that the combination of a WEE1 inhibitor (AZD1775), irinotecan, and vincristine can lead to complete response in multiple rhabdomyosarcoma orthotopic patient-derived xenografts tumours in vivo.
Project description:Robust patient-derived platforms that recapitulate the cellular and molecular fingerprints of glioblastoma are crucial for developing effective therapies. Here, we describe a chemically defined protocol for 3D culture and propagation of glioblastoma in 3D gliospheres, patient-derived organoids (PDOs), mouse brain orthotopic xenografts (PDOXs), and downstream drug and immunofluorescence assays. This simple-to-follow protocol allows assessing drug sensitivity, on-target activity, and combined drug synergy. Promising therapies can then be validated in PDOXs for translation in precision medicine oncology trials. For complete details on the use and execution of this protocol, please refer to Chadwick et al. (2020) and Patrizii et al. (2018).
Project description:Tumors from 25 patients with pancreatic cancer were used to establish two patient-derived xenograft (PDX) models: orthotopic PDX (PDOX) and heterotopic (subcutaneous) PDX (PDHX). We compared gene expression by immunohistochemistry, single-nucleotide polymorphism (SNP), DNA methylation, and metabolite levels. The 4 cases, of the total of 13 in which simultaneous PDHX & PDOX models were established, were randomly selected. The molecular-genetic characteristics of the patient's tumor were well maintained in the two PDX models. SNP analysis demonstrated that both groups were more than 90% identical to the original patient's tumor, and there was little difference between the two models. DNA methylation of most genes was similar among the two models and the original patients tumor, but some gene sets were hypermethylated the in PDOX model and hypomethylated in the PDHX model. Most of the metabolites had a similar pattern to those of the original patient tumor in both PDX tumor models, but some metabolites were more prominent in the PDOX and PDHX models. This is the first simultaneous molecular-genetic and metabolite comparison of patient tumors and their tumors established in PDOX and PDHX models. The results indicate high fidelity of these critical properties of the patient tumors in the two models.
Project description:Despite extensive research, little progress has been made in glioblastoma therapy, owing in part to a lack of adequate preclinical in vivo models to study this disease. To mitigate this, primary patient-derived cell lines, which maintain their specific stem-like phenotypes, have replaced established glioblastoma cell lines. However, due to heterogenous tumour growth inherent in glioblastoma, the use of primary cells for orthotopic in vivo studies often requires large experimental group sizes. Therefore, when using intracranial patient-derived xenograft (PDX) approaches, it is advantageous to deploy imaging techniques to monitor tumour growth and allow stratification of mice. Here we show that stable expression of near-infrared fluorescent protein (iRFP) in patient-derived glioblastoma cells enables rapid, direct non-invasive monitoring of tumour development without compromising tumour stemness or tumorigenicity. Moreover, as this approach does not depend on the use of agents like luciferin, which can cause variability due to changing bioavailability, it can be used for quantitative longitudinal monitoring of tumour growth. Notably, we show that this technique also allows quantitative assessment of tumour burden in highly invasive models spreading throughout the brain. Thus, iRFP transduction of primary patient-derived glioblastoma cells is a reliable, cost- and time-effective way to monitor heterogenous orthotopic PDX growth.
Project description:BACKGROUND:Patient-derived xenograft (PDX) models are in vivo models of human cancer that have been used for translational cancer research and therapy selection for individual patients. The Jackson Laboratory (JAX) PDX resource comprises 455 models originating from 34 different primary sites (as of 05/08/2019). The models undergo rigorous quality control and are genomically characterized to identify somatic mutations, copy number alterations, and transcriptional profiles. Bioinformatics workflows for analyzing genomic data obtained from human tumors engrafted in a mouse host (i.e., Patient-Derived Xenografts; PDXs) must address challenges such as discriminating between mouse and human sequence reads and accurately identifying somatic mutations and copy number alterations when paired non-tumor DNA from the patient is not available for comparison. RESULTS:We report here data analysis workflows and guidelines that address these challenges and achieve reliable identification of somatic mutations, copy number alterations, and transcriptomic profiles of tumors from PDX models that lack genomic data from paired non-tumor tissue for comparison. Our workflows incorporate commonly used software and public databases but are tailored to address the specific challenges of PDX genomics data analysis through parameter tuning and customized data filters and result in improved accuracy for the detection of somatic alterations in PDX models. We also report a gene expression-based classifier that can identify EBV-transformed tumors. We validated our analytical approaches using data simulations and demonstrated the overall concordance of the genomic properties of xenograft tumors with data from primary human tumors in The Cancer Genome Atlas (TCGA). CONCLUSIONS:The analysis workflows that we have developed to accurately predict somatic profiles of tumors from PDX models that lack normal tissue for comparison enable the identification of the key oncogenic genomic and expression signatures to support model selection and/or biomarker development in therapeutic studies. A reference implementation of our analysis recommendations is available at https://github.com/TheJacksonLaboratory/PDX-Analysis-Workflows .
Project description:Neuroblastoma is a childhood tumour with heterogeneous characteristics and children with metastatic disease often have a poor outcome. Here we describe the establishment of neuroblastoma patient-derived xenografts (PDXs) by orthotopic implantation of viably cryopreserved or fresh tumour explants of patients with high risk neuroblastoma into immunodeficient mice. In vivo tumour growth was monitored by magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography. Neuroblastoma PDXs retained the undifferentiated histology and proliferative capacity of their corresponding patient tumours. The PDXs expressed neuroblastoma markers neural cell adhesion molecule, chromogranin A, synaptophysin and tyrosine hydroxylase. Whole genome genotyping array analyses demonstrated that PDXs retained patient-specific chromosomal aberrations such as MYCN amplification, deletion of 1p and gain of chromosome 17q. Thus, neuroblastoma PDXs recapitulate the hallmarks of high-risk neuroblastoma in patients. PDX-derived cells were cultured in serum-free medium where they formed free-floating neurospheres, expressed neuroblastoma gene markers MYCN, CHGA, TH, SYP and NPY, and retained tumour-initiating and metastatic capacity in vivo. PDXs showed much higher degree of infiltrative growth and distant metastasis as compared to neuroblastoma SK-N-BE(2)c cell line-derived orthotopic tumours. Importantly, the PDXs presented with bone marrow involvement, a clinical feature of aggressive neuroblastoma. Thus, neuroblastoma PDXs serve as clinically relevant models for studying and targeting high-risk metastatic neuroblastoma.