Project description:Distinct endothelial cell cycle states (early G1 vs. late G1) provide different “windows of opportunity” to enable the differential expression of genes that regulate venous and arterial specification, respectively. Endothelial cell cycle control and arterial-venous identities are disrupted in vascular malformations including arteriovenous (AV) shunts which is a hallmark of hereditary hemorrhagic telangiectasia (HHT). We show how endothelial cell late G1 arrest induced by Palbociclib modulates the expression of genes regulating arterio-venous identity and prevents AVM development induced by BMP9/10 inhibition.
Project description:Hereditary hemorrhagic telangiectasia (HHT) is a rare autosomal dominant vascular dysplasia characterized by epistaxis, mucocutaneous telangiectases, and arteriovenous malformations (AVM) in visceral organs. In this study, we carried out a liquid biopsy consisting in the isolation of total RNA from plasma exosomes samples from HHT type 1 (HHT1 group) and type 2 (HHT2 group) patients, and healthy relatives (Control group). Upon gene expression data processing and normalization, a bioinformatics analysis was performed for the study of principal components, hierarchical clustering and pairwise comparisons between HHT samples and control group. Results were evaluated in a further validation cohort of HHT and healthy donors by real time PCR and the diagnosis value of exosomal miRNA determined by the ROC curves analysis. We found that exosomal miRNA expression signature clearly distinguishes among healthy and HHT samples and types. Thus, we identified a disease-associated molecular fingerprint of 35 miRNAs over-represented, being 8 specifics for HHT1 and 11 for HHT2; and 30 under-represented, including 9 distinctive for HHT1 and 9 for HHT2. These exosome-transported miRNAs have diagnosis value for HHT, and even allow to distinguish between HHT1 and HHT2.
Project description:The etiology of trauma-hemorrhage shock-induced acute lung injury has been difficult to elucidate due, at least in part, to the inability of in vivo studies to separate the non-injurious pulmonary effects of trauma-hemorrhage from the tissue injurious ones. To circumvent this in vivo limitation, we utilized a model of trauma-hemorrhagic shock (T/HS) in which T/HS-lung injury was abrogated by dividing the mesenteric lymph duct. In this way, it was possible to separate the pulmonary injurious response from the non-injurious systemic response to T/HS by comparing the pulmonary molecular response of rats subjected to T/HS which did and did not develop lung injury as well as to non-shocked rats. Utilizing high-density oligonucleotide arrays and treatment group comparisons of whole lung tissue collected at 3 hours after the end of the shock or sham-shock period, 139 of the 8,799 assessed genes were differentially expressed. Experiment Overall Design: Four groups of rats (n=3) were studied in order to identify changes in pulmonary gene expression associated with T/HS, both in the presence and absence of lung injury. These included trauma-sham shock (T/SS) rats which had a laparotomy (trauma) but were not subjected to hemorrhagic shock. These rats had no lung injury and served as controls for rats which were subjected to T/HS (laparotomy plus 90 min of shock) and had lung injury. Differences in gene expression between these two groups would represent both the effects of hemorrhagic shock as well as lung injury. To distinguish the gene response of hemorrhagic shock from the gene response associated with lung injury, gene expression was also compared between T/HS rats (hemorrhage and lung injury) and rats subjected to T/HS plus lymph duct ligation (T/HS-LDL), since the T/HS-LDL rats experienced hemorrhagic shock but had no measurable lung injury. Lastly, to identify hemorrhagic shock- modified genes, the pulmonary gene response of T/HS-LDL (hemorrhage without lung injury) were compared to rats subjected to T/SS plus LDL (no hemorrhage or lung injury). Three hours after the end of the 90 min shock or sham-shock period (i.e. 4.5 hrs after the induction of T/HS), the rats were sacrificed and specimens harvested for genechip analysis and histology.
Project description:Hereditary Haemorrhagic Telangiectasia (HHT) is an autosomal dominantly inherited vascular disease characterized by the presence of mucocutaneous telangiectasia and arteriovenous malformations in visceral organs. HHT is predominantly caused by mutations in ENG and ACVRL1, Which both belong to the TGF-M-NM-2 signalling pathway. Further knowledge on how a disturbance of the TGF-M-NM-2 signalling pathway leads to HHT manifestations is needed in order to identify potential therapeutic targets. As long non-coding RNAs (lncRNAs) are increasingly recognized as key regulators of gene expression and constitute a sizable fraction of the human transcriptome, we wanted to assess whether lncRNAs play a role in the molecular pathogenesis of HHT. Here we used microarray analysis to profile lncRNAs to compare the expression of HHT telangiectasial and HHT non-telangiectasial nasal tissue from the same patient in a paired design. The microarray probes were re-annotated using the GENCODE v.16 dataset, identifying 4,810 probes mapping to 2,811 lncRNAs. By comparing HHT telangiectasial tissue versus HHT non-telangiectasial tissue, we identified 42 lncRNAs that are differentially expressed (q<0.001). Using GREAT, a tool that assumes cis-regulation, we showed that differently expressed lncRNAs are enriched for genomic loci involved in key pathways concerning HHT. Our study identified lncRNAs that are aberrantly expressed in HHT telangiectasia and indicates that lncRNAs may contribute to regulate protein-coding loci in HHT. Which suggest that the lncRNA component of the transcriptome deserves more attention in HHT. A deeper understanding of lncRNAs and their role in telangiectasia formation possesses potential for discovering therapeutic targets in HHT. Gene expression profiling of 80 paired nasal samples from patients with hereditary Haemorrhagic Telangiectasia (HHT), representing telangiectasial and non-telangiectasial (normal) tissue respectively. The patients were divided into HHT1 or HHT2 in regard to the germline mutation in ENG (HHT1) or ACVRL1 (HHT2). Additional controls were healthy siblings (not carrying the germline mutation) and external controls. The study was conducted using Agilent-028004 SurePrint G3 Human GE 8x60K Microarray platform.
Project description:Hereditary Haemorrhagic Telangiectasia (HHT) is an autosomal dominantly inherited vascular disease characterized by the presence of mucocutaneous telangiectasia and arteriovenous malformations in visceral organs. HHT is predominantly caused by mutations in ENG and ACVRL1, Which both belong to the TGF-β signalling pathway. Further knowledge on how a disturbance of the TGF-β signalling pathway leads to HHT manifestations is needed in order to identify potential therapeutic targets. As long non-coding RNAs (lncRNAs) are increasingly recognized as key regulators of gene expression and constitute a sizable fraction of the human transcriptome, we wanted to assess whether lncRNAs play a role in the molecular pathogenesis of HHT. Here we used microarray analysis to profile lncRNAs to compare the expression of HHT telangiectasial and HHT non-telangiectasial nasal tissue from the same patient in a paired design. The microarray probes were re-annotated using the GENCODE v.16 dataset, identifying 4,810 probes mapping to 2,811 lncRNAs. By comparing HHT telangiectasial tissue versus HHT non-telangiectasial tissue, we identified 42 lncRNAs that are differentially expressed (q<0.001). Using GREAT, a tool that assumes cis-regulation, we showed that differently expressed lncRNAs are enriched for genomic loci involved in key pathways concerning HHT. Our study identified lncRNAs that are aberrantly expressed in HHT telangiectasia and indicates that lncRNAs may contribute to regulate protein-coding loci in HHT. Which suggest that the lncRNA component of the transcriptome deserves more attention in HHT. A deeper understanding of lncRNAs and their role in telangiectasia formation possesses potential for discovering therapeutic targets in HHT.
Project description:Hereditary hemorrhagic telangiectasia (HHT) is a systemic disease characterized by mucocutaneous telangiectasias, epistaxis, and arteriovenous malformations (AVMs). Intracranial hemorrhage (ICH) rates in this population are not well described. We report ICH rates and characteristics in HHT patients with brain AVMs (HHT-BAVMs).We studied the first 153 HHT-BAVM patients with follow-up data enrolled in the Brain Vascular Malformation Consortium HHT Project. We estimated ICH rates after BAVM diagnosis.The majority of patients were women (58%) and white (98%). The mean age at BAVM diagnosis was 31±19 years (range, 0-70), with 61% of cases diagnosed on asymptomatic screening. Overall, 14% presented with ICH; among symptomatic cases, 37% presented ruptured. During 493 patient-years of follow-up, 5 ICH events occurred yielding a rate of 1.02% per year (95% confidence interval, 0.42-2.44%). ICH-free survival differed significantly by ICH presentation (P=0.003); ruptured cases had a higher ICH rate (10.07%; 95% confidence interval, 3.25-31.21%) than unruptured cases (0.43%; 95% confidence interval, 0.11-1.73%).Patients with HHT-BAVM who present with hemorrhage are at a higher risk for rehemorrhage compared with patients with BAVM detected presymptomatically.