Characterization of Differential Gene Expression in Quiescent and Invasive Human Arterial Smooth Muscle Cells

Abstract

Proliferation, migration and invasion of smooth muscle cells (SMCs) are essential pathogenic processes in the development of a broad spectrum of cardiovascular disorders, like arteriosclerosis, restenosis after percutaneous transluminal angioplasty and stent implantation as well as transplant vessel disease. As an in vitro model mimicking these processes, the Boyden chamber was employed to characterize the diverging migratory and invasive potentials of proliferating and nonproliferating human arterial SMCs (haSMCs). Using this model, differential gene expression of both phenotypes was analyzed by a cDNA array system (Clontech human cardiovascular array). With these arrays, 558 cardiovascular-associated genes could be compared. Further, gene expression was exactly quantified by real-time RT-PCR. Protein expression was analyzed by ELISA and Western blotting. In total, 47 genes were differentially expressed more than 1.5 times. Most of the differentially regulated genes in this study were associated with the extracellular matrix (ECM) and cell motility. In detail, the respective groups were matrix-organizing proteins, ECM proteins, cell adhesion proteins, extracellular communication and cytoskeleton motility proteins. Genes known to be differentially regulated during haSMC migration and invasion, like TIMP 2, TIMP 3, and MMP 3, were confirmed by the array data. Reduced expression of several cytoskeletal proteins, like vimentin, fibronectin, cytokeratins and β1 integrin, was shown in the invasive phenotype. Further, angio-associated protein, alpha E-catenin and atrial brain natriuretic peptide receptor were downregulated whereas TFPI 2 was strongly upregulated in invasive haSMCs. In conclusion, several relevant potential candidate genes for the quiescent and the invasive SMC phenotype were identified and genes already known to be differentially regulated by previous analysis were confirmed.

Divergent effects of matrix metalloproteinases 3, 7, 9, and 12 on atherosclerotic plaque stability in mouse brachiocephalic arteries

“…Galis and colleagues (3) showed that all of the smooth muscle cells in human atherosclerotic lesions, and the majority of those in the media, express MMP-3 protein. It has been suggested MMP-3 facilitates the degradation of cell-to-matrix and cell-to-cell contacts during proliferation and migration of smooth muscle cells (19)(20)(21)(22), and in the current study there were indeed fewer smooth muscle cells in atherosclerotic lesions from apoE͞MMP-3 double knockout mice than controls (Table 3). …”

Physiological Genomics of Human Arteries

“…Recent studies, indeed, show a strong correlation between PWV and subclinical atherosclerosis. 13,14 Among the identified genes of the present study, several could be directly implicated in atherosclerosis such as decorin, 15 protein kinase ␤ 1 , 16 catenin, 17 and integrins ␣ v ␤ 3 , triggering activation of PI3 kinase. 18 …”

Matrix Metalloproteinase (MMP)-3 Activates MMP-9 Mediated Vascular Smooth Muscle Cell Migration and Neointima Formation in Mice

“…MMP-3 and MMP-9 are also coordinately upregulated by growth factors and inflammatory cytokines in rat VSMCs. 48 Moreover, MMP-3 and MMP-9 are both upregulated coincident with VSMC migration during the first week after balloon injury in several species 49 and it has also been shown that MMP-3 expression is regulated during VSMC migration and invasion 50 and is increased 3 days after carotid ligation in C57Bl6/J mice. 9 Moreover, MMP-3 expression precedes MMP-9 expression after balloon angioplasty of the rat carotid artery.…”