title: Unraveling divergent gene expression profiles in bicuspid and tricuspid aortic valve patients with thoracic aortic dilatation: the ASAP study.
abstract: Thoracic aortic aneurysm (TAA) is a common complication in patients with a bicuspid aortic valve (BAV), the most frequent congenital heart disorder. For unknown reasons TAA occurs at a younger age, with a higher frequency in BAV patients than in patients with a tricuspid aortic valve (TAV), resulting in an increased risk for aortic dissection and rupture. To investigate the increased TAA incidence in BAV patients, we obtained tissue biopsy samples from nondilated and dilated aortas of 131 BAV and TAV patients. Global gene expression profiles were analyzed from controls and from aortic intima-media and adventitia of patients (in total 345 samples). Of the genes found to be differentially expressed with dilation, only a few (<4%) were differentially expressed in both BAV and TAV patients. With the use of gene set enrichment analysis, the cell adhesion and extracellular region gene ontology sets were identified as common features of TAA in both BAV and TAV patients. Immune response genes were observed to be particularly overexpressed in the aortic media of dilated TAV samples. The divergent gene expression profiles indicate that there are fundamental differences in TAA etiology in BAV and TAV patients. Immune response activation solely in the aortic media of TAV patients suggests that inflammation is involved in TAA formation in TAV but not in BAV patients. Conversely, genes were identified that were only differentially expressed with dilation in BAV patients. The result has bearing on future clinical studies in which separate analysis of BAV and TAV patients is recommended.
authors.affiliation: Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Lasse
authors.initials: L
authors.lastname: Folkersen
authors.forename: Dick
authors.initials: D
authors.lastname: Wågsäter
authors.forename: Valentina
authors.initials: V
authors.lastname: Paloschi
authors.forename: Veronica
authors.initials: V
authors.lastname: Jackson
authors.forename: Johan
authors.initials: J
authors.lastname: Petrini
authors.forename: Sanela
authors.initials: S
authors.lastname: Kurtovic
authors.forename: Shohreh
authors.initials: S
authors.lastname: Maleki
authors.forename: Maria J
authors.initials: MJ
authors.lastname: Eriksson
authors.forename: Kenneth
authors.initials: K
authors.lastname: Caidahl
authors.forename: Anders
authors.initials: A
authors.lastname: Hamsten
authors.forename: Jean-Baptiste
authors.initials: JB
authors.lastname: Michel
authors.forename: Jan
authors.initials: J
authors.lastname: Liska
authors.forename: Anders
authors.initials: A
authors.lastname: Gabrielsen
authors.forename: Anders
authors.initials: A
authors.lastname: Franco-Cereceda
authors.forename: Per
authors.initials: P
authors.lastname: Eriksson
mesh_terms: D000368:Aged; D001013:Aorta, Thoracic / Q000378:metabolism / Q000473:pathology*; D017545:Aortic Aneurysm, Thoracic / Q000150:complications / Q000235:genetics* / Q000276:immunology; D015415:Biomarkers / Q000378:metabolism; D015704:CD4 Antigens / Q000378:metabolism; D030541:Databases, Genetic; D004108:Dilatation, Pathologic; D005260:Female; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006349:Heart Valve Diseases / Q000150:complications / Q000235:genetics* / Q000276:immunology; D006801:Humans; D007109:Immunity / Q000235:genetics; D007150:Immunohistochemistry; D007249:Inflammation / Q000150:complications / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D008943:Mitral Valve / Q000378:metabolism / Q000473:pathology*; D025341:Principal Component Analysis; D015203:Reproducibility of Results; D015398:Signal Transduction / Q000235:genetics; D014261:Tricuspid Valve / Q000378:metabolism / Q000473:pathology*; D017539:Tunica Intima / Q000378:metabolism / Q000473:pathology; D017540:Tunica Media / Q000378:metabolism / Q000473:pathology
chemical_list: D015415:Biomarkers; D015704:CD4 Antigens