Project description:Glioblastoma multiforme (GBM) brain tumours have one of the shortest mean survival times (<1 year). In vivo models of GBM in mice and rats have been developed to study aspects of glioma that cannot be observed in cell culture such as angiogenesis, invasion and metastasis. Gliomas can be induced by implantation of rodent glioma cell lines into the brain or flank of nude mice. The disadvantages of rodent models however include variable growth rate and poor penetrance, which leads to difficulties in collecting clearly graded samples (pre-vascular/vascular). Bikfalvi et al have previously established a human GBM model that addresses these issues based on the chicken egg chorio-allantoic membrane (CAM), a highly vascularised extra-embryonic tissue. We have used DNA microarrays and a CAM model of GBM to study gene expression during the recruitment and development of the tumour vasculature. Over a 5 day period samples were taken every 12 hours from the tumour implantation site consisting of tumour cells and stroma cells, and also from a site distant from the implantation site consisting of just CAM cells. This study will shed light on the dynamic transcriptional signature of pathological angiogenesis. On day 10 of embryonic development 3-5 million U87 cells were deposited onto the surface of the CAM after gentle laceration. The cells were contained within a plastic ring and each tumour was size matched based on its volume. Tumour/stroma and distant CAM samples were cut out at 12 hour intervals post implantation for 5 days, equalling 10 time points. Each time point consisted of three replicates. U87 cells in culture (pre-implantation) were also included in the study in triplicate.
Project description:Glioblastoma multiforme (GBM) brain tumours have one of the shortest mean survival times (<1 year). In vivo models of GBM in mice and rats have been developed to study aspects of glioma that cannot be observed in cell culture such as angiogenesis, invasion and metastasis. Gliomas can be induced by implantation of rodent glioma cell lines into the brain or flank of nude mice. The disadvantages of rodent models however include variable growth rate and poor penetrance, which leads to difficulties in collecting clearly graded samples (pre-vascular/vascular). Bikfalvi et al have previously established a human GBM model that addresses these issues based on the chicken egg chorio-allantoic membrane (CAM), a highly vascularised extra-embryonic tissue. We have used DNA microarrays and a CAM model of GBM to study gene expression during the recruitment and development of the tumour vasculature. Over a 5 day period samples were taken every 12 hours from the tumour implantation site consisting of tumour cells and stroma cells, and also from a site distant from the implantation site consisting of just CAM cells. This study will shed light on the dynamic transcriptional signature of pathological angiogenesis.
Project description:Glioblastoma multiforme (GBM) brain tumours have one of the shortest mean survival times (<1 year). In vivo models of GBM in mice and rats have been developed to study aspects of glioma that cannot be observed in cell culture such as angiogenesis, invasion and metastasis. Gliomas can be induced by implantation of rodent glioma cell lines into the brain or flank of nude mice. The disadvantages of rodent models however include variable growth rate and poor penetrance, which leads to difficulties in collecting clearly graded samples (pre-vascular/vascular). Bikfalvi et al have previously established a human GBM model that addresses these issues based on the chicken egg chorio-allantoic membrane (CAM), a highly vascularised extra-embryonic tissue. We have used DNA microarrays and a CAM model of GBM to study gene expression during the recruitment and development of the tumour vasculature. Over a 5 day period samples were taken every 12 hours from the tumour implantation site consisting of tumour cells and stroma cells, and also from a site distant from the implantation site consisting of just CAM cells. This study will shed light on the dynamic transcriptional signature of pathological angiogenesis. On day 10 of embryonic development 3-5 million U87 cells were deposited onto the surface of the CAM after gentle laceration. The cells were contained within a plastic ring and each tumour was size matched based on its volume. Tumour/stroma and distant CAM samples were cut out at 12 hour intervals post implantation for 5 days, equalling 10 time points. Each time point consisted of three replicates. U87 cells in culture (pre-implantation) were also included in the study in triplicate.
Project description:Human pancreatic adenocarcinoma cells were grafted on the chick chorioallantoic membrane (CAM). Human and chicken GeneChips were used simultaneously to study gene regulation during PDAC cell invasion.
Project description:Human pancreatic adenocarcinoma cells were grafted on the chick chorioallantoic membrane (CAM). Human and chicken GeneChips were used simultaneously to study gene regulation during PDAC cell invasion. Experiment Overall Design: Pooled RNA from T1 (n=3) and T6 (n=3) CAMs were extracted using the RNeasy mini kit (Qiagen). T6 was compared to T1 on human GeneChips and in parallel, on chicken GeneChips.
Project description:We determined gene expression profiles which were induced in the chick chorio-allantoic membrane 24 h after application of recombinant human VEGF.
Project description:Modern functional genomic approaches may help to better understand the molecular events involved in tissue morphogenesis and to identify molecular signatures and pathways. We have recently applied transcriptomic profiling to evidence molecular signatures in the development of the normal chicken chorioallantoic membrane and in tumor engrafted on the CAM. We have now extended our studies by performing a transcriptome analysis in the wound model of the chicken CAM which is another relevant model of tissue morphogenesis. To induce granulation tissue formation, we performed wounding of the chicken CAM and compared gene expression to normal CAM at the same stage of development. Matched control samples from the same individual were used. We observed a total of 282 genes up-regulated and 44 genes downregulated assuming a false-discovery rate at 5 % and a fold change > 2. Furthermore, bioinformatics analysis lead to the identification of several categories that are associated to organismal injury, tissue morphology, cellular movement, inflammatory disease, development and immune system. Endothelial cell data filtering leads to the identification of several new genes with an endothelial cell signature. In summary, the chick chorioallantoic wound model allows the identification of gene signatures involved in granulation tissue formation and neoangiogenesis. This may constitute a fertile ground for further studies. CAM tissue from brown leghorn eggs was excised from three Control and Wound groups.
Project description:In this study the transcription profile of bovine trophoblastic cells infected with Brucella samples was evaluated. Chorioallantoic membrane (CAM) explants inoculated with wild type (strain 2308), and to compare with the transcription profile of trophoblastic cells infected with mutant strains lacking virB2 or btpB.M-NM-^TvirB2 or M-NM-^TbtpB by microarray analysis at 4 hours post infection. Genes with significant variation in levels of transcripts (fold change > 2 and P < 0.05) were functionally classified, and transcripts related to defense and inflammation were assessed by quantitative real time RT-PCR. Chorioallantoic membrane explant culture (CAM) were obtained from 7 intact pregnant bovine uteruses at the final third of gestation. Three-condition experiment, wild type B. abortus 2308, DvirB2 or DbtpB in 4 control replicates and Microarray analysis.
Project description:In chickens, embryonic development begins upon egg formation and lasts for 21 days of incubation until hatching. The CAM is an extraembryonic membrane that serves a critical role in acid-base balance, gaseous exchange, calcium solubilization, and antimicrobial protection. Comparative proteomic analyses of CAM at two developmental stages (ED12 and ED19), in comparison to the proteome of embryonic blood serum, revealed protein groups that are relatively or highly specific to the CAM. The specific CAM functions include gaseous exchange, Ca2+ transport, vasculature development, and protection against pathogen invasion. Overall, our results highlight the structure-function relationship of the CAM protein constituents that potentially could expand its biomedical applications.
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.