Project description:Hypoxia episodes and areas in tumours have been associated with metastatic dissemination and poor prognosis. Given the link between tumour tissue oxygen levels and cellular metabolic activity, we hypothesised that the metabolic profile between metastatic and non-metastatic tumours would reveal potential new biomarkers and signalling cues. We have used a previously established chick embryo model for neuroblastoma growth and metastasis, where the metastatic phenotype can be controlled by neuroblastoma cell hypoxic preconditioning (3 days at 1% O2). We measured, with fibre-optic oxygen sensors, the effects of the hypoxic preconditioning on the tumour oxygenation, within tumours formed by SK-N-AS cells on the chorioallantoic membrane (CAM) of chick embryos. We found that the difference between the metastatic and non-metastatic intratumoural oxygen levels was small (0.35% O2), with a mean below 1.5% O2 for most tumours. The metabolomic profiling, using NMR spectroscopy, of neuroblastoma cells cultured in normoxia or hypoxia for 3 days, and of the tumours formed by these cells showed that the effects of hypoxia in vitro did not compare with in vivo tumours. One notable difference was the high levels of the glycolytic end-products triggered by hypoxia in vitro, but not by hypoxia preconditioning in tumours, likely due to the very high basal levels of these metabolites in tumours compared with cells. In conclusion, we have identified high levels of ketones (3-hydroxybutyrate), lactate and phosphocholine in hypoxic preconditioned tumours, all known to fuel tumour growth, and we herein point to the poor relevance of in vitro metabolomic experiments for cancer research.
Project description:The transcription factor FOXR2 is the universal driver of childhood central nervous system neuroblastoma, FOXR2 activated (NB-FOXR2). NB-FOXR2 tumors arise exclusively in the brain hemispheres, and despite morphological similarities to other pediatric brain tumors, they are a molecularly distinct entity based on DNA methylation profiling. The cell-of-origin is unknown. Here, we profiled a cohort of rare NB-FOXR2 tumors by bulk and single-cell transcriptomics. Through systematic comparative analyses, we delineate tumor transcriptional states and candidate cell-of-origin. More broadly, we demonstrate systematic molecular profiling of childhood cancers to orient oncogenic targeting for in vivo modeling, a critical resource for the study of rare tumors and development of therapeutics.
Project description:The transcription factor FOXR2 is the universal driver of childhood central nervous system neuroblastoma, FOXR2 activated (NB-FOXR2). NB-FOXR2 tumors arise exclusively in the brain hemispheres, and despite morphological similarities to other pediatric brain tumors, they are a molecularly distinct entity based on DNA methylation profiling. The cell-of-origin is unknown. Here, we profiled a cohort of rare NB-FOXR2 tumors by bulk and single-cell transcriptomics. Through systematic comparative analyses, we delineate tumor transcriptional states and candidate cell-of-origin. More broadly, we demonstrate systematic molecular profiling of childhood cancers to orient oncogenic targeting for in vivo modeling, a critical resource for the study of rare tumors and development of therapeutics.
Project description:The transcription factor FOXR2 is the universal driver of childhood central nervous system neuroblastoma, FOXR2 activated (NB-FOXR2). NB-FOXR2 tumors arise exclusively in the brain hemispheres, and despite morphological similarities to other pediatric brain tumors, they are a molecularly distinct entity based on DNA methylation profiling. The cell-of-origin is unknown. Here, we profiled a cohort of rare NB-FOXR2 tumors by bulk and single-cell transcriptomics. Through systematic comparative analyses, we delineate tumor transcriptional states and candidate cell-of-origin. More broadly, we demonstrate systematic molecular profiling of childhood cancers to orient oncogenic targeting for in vivo modeling, a critical resource for the study of rare tumors and development of therapeutics.
Project description:Analysis of differential gene expression in HeLa Parental vs radio-resistant xenograft tumours. The aim is to identify potential genes that are deregulated in radio-resistant tumours.
Project description:Embryonal tumours of the central nervous system (CNS) represent a heterogeneous group of tumours about which little is known biologically, and whose diagnosis, on the basis of morphologic appearance alone, is controversial. Medulloblastomas, for example, are the most common malignant brain tumour of childhood, but their pathogenesis is unknown, their relationship to other embryonal CNS tumours is debated, and patients' response to therapy is difficult to predict. We approached these problems by developing a classification system based on DNA microarray gene expression data derived from 99 patient samples. Here we demonstrate that medulloblastomas are molecularly distinct from other brain tumours including primitive neuroectodermal tumours (PNETs), atypical teratoid/rhabdoid tumours (AT/RTs) and malignant gliomas. Previously unrecognized evidence supporting the derivation of medulloblastomas from cerebellar granule cells through activation of the Sonic Hedgehog (SHH) pathway was also revealed. We show further that the clinical outcome of children with medulloblastomas is highly predictable on the basis of the gene expression profiles of their tumours at diagnosis.
Project description:Molecular defects in some ultra-rare subtypes of familial lipodystrophies remain unidentified. We identified novel NOTCH3 heterozygous variants in familial partial lipodystrophy (FPL) pedigrees. All variants were clustered in the heterodimerization domain of the negative regulatory region of NOTCH3. Proteomics of skin fibroblasts revealed significantly higher RNA expression of NOTCH3 and activation of widespread senescence pathways in the FPL patients versus controls.
Project description:Pituitary neuroendocrine tumours (PitNET) are rare neoplasms of the pituitary gland that can overproduce pituitary hormones or cause headaches and visual impairment due to mass effect. Growth hormone overproducing somatotroph PitNETs cause acromegaly leading to wide range of connective tissue, metabolic and oncologic disorders. The medical treamment of acromegaly is somatostin analogues (SSA) in specific cases combined with dopamine agnoists (DA), but almost half of patients excert SSA resistence and potential causes of this is unknown. The aim of this study was to characterize transcriptomic patterns of somatotroph PitNETs specifically assessing impact of SSA treatment effects. We investigated gene expession on several levels and functional models of GH PitNETs - tumour tissue of patients with and without SSA preoperative treamtment, tumour derived pituisphere model and classically used GH3 cell line treated with SSA.