title: Global gene expression profiling of telangiectasial tissue from patients with hereditary hemorrhagic telangiectasia.
abstract: Hereditary hemorrhagic telangiectasia (HHT), the most common inherited vascular disorder, is predominantly caused by mutations in ENG and ACVRL1, which are part of the transforming growth factor beta (TGF-β) signaling pathway. HHT is characterized by the presence of mucocutaneous telangiectases and arteriovenous malformations in visceral organs, primarily the lungs, brain and liver. The most common symptom in HHT is epistaxis originating from nasal telangiectasia, which can be difficult to prevent and can lead to severe anemia. The clinical manifestations of HHT are extremely variable, even within family members, and the exact mechanism of how endoglin and ALK1 haploinsufficiency leads to HHT manifestations remains to be identified.
  
  
  OBJECTIVE
  The purpose of this study was to detect significantly differentially regulated genes in HHT, and try to elucidate the pathways and regulatory mechanisms occurring in the affected tissue of HHT patients, in order to further characterize this disorder and hypothesize on how telangiectases develop. By microarray technology (Agilent G3 Human GE 8x60), we performed global gene expression profiling of mRNA transcripts from HHT nasal telangiectasial (n = 40) and non-telangiectasial (n = 40) tissue using a paired design. Comparing HHT telangiectasial and non-telangiectasial tissue, significantly differentially expressed genes were detected using a paired t-test. Gene set analysis was performed using GSA-SNP. In the group of ENG mutation carriers, we detected 67 differentially expressed mRNAs, of which 62 were down-regulated in the telangiectasial tissue. Gene set analysis identified the gene ontology (GO) terms vasculogenesis, TGF-β signaling, and Wnt signaling as differentially expressed in HHT1. Altered Wnt signaling might be related to HHT pathogenesis and a greater understanding of this may lead to the discovery of therapeutic targets in HHT.
authors.affiliation: Department of Clinical Genetics, Odense University Hospital, Denmark; Otorhinolaryngology, Institute of Clinical Research, University of Southern Denmark, Denmark. Electronic address: pernille.toerring@rsyd.dk.
authors.forename: Pernille M
authors.initials: PM
authors.lastname: Tørring
authors.affiliation: Department of Clinical Genetics, Odense University Hospital, Denmark; Human Genetics, Institute of Clinical Research, University of Southern Denmark, Denmark.
authors.forename: Martin Jakob
authors.initials: MJ
authors.lastname: Larsen
authors.affiliation: Department of Otorhinolaryngology, Odense University Hospital, Denmark; Otorhinolaryngology, Institute of Clinical Research, University of Southern Denmark, Denmark.
authors.forename: Anette D
authors.initials: AD
authors.lastname: Kjeldsen
authors.affiliation: Department of Clinical Genetics, Odense University Hospital, Denmark; Human Genetics, Institute of Clinical Research, University of Southern Denmark, Denmark.
authors.forename: Lilian Bomme
authors.initials: LB
authors.lastname: Ousager
authors.affiliation: Department of Clinical Genetics, Odense University Hospital, Denmark; Epidemiology, Biostatistics and Biodemography, Institute of Public Health, University of Southern Denmark, Denmark.
authors.forename: Qihua
authors.initials: Q
authors.lastname: Tan
authors.affiliation: Department of Clinical Genetics, Odense University Hospital, Denmark; Human Genetics, Institute of Clinical Research, University of Southern Denmark, Denmark.
authors.forename: Klaus
authors.initials: K
authors.lastname: Brusgaard
mesh_terms: D030301:Activin Receptors, Type II / Q000235:genetics*; D015703:Antigens, CD / Q000235:genetics*; D001165:Arteriovenous Malformations / Q000235:genetics; D001706:Biopsy; D016000:Cluster Analysis; D000071063:Endoglin; D005192:Family Health; D005260:Female; D020869:Gene Expression Profiling; D005838:Genotype; D006801:Humans; D008297:Male; D009154:Mutation; D009297:Nasal Mucosa / Q000473:pathology; D009693:Nucleic Acid Hybridization; D025341:Principal Component Analysis; D011956:Receptors, Cell Surface / Q000235:genetics*; D015398:Signal Transduction; D013683:Telangiectasia, Hereditary Hemorrhagic / Q000235:genetics*; D016212:Transforming Growth Factor beta / Q000378:metabolism
chemical_list: D015703:Antigens, CD; C064206:ENG protein, human; D000071063:Endoglin; D011956:Receptors, Cell Surface; D016212:Transforming Growth Factor beta; C425364:ACVRL1 protein, human; D030301:Activin Receptors, Type II
keywords: Gene expression profiling; HHT; Hereditary haemorrhagic telangiectasia; RNA microarray profiling; TGFbeta signalling