Increased chemotactic migration and growth in heparanase-overexpressing human U251n glioma cells

Department of Neurology, Henry Ford Health Science Center, Detroit, MI, USA.
Journal of Experimental & Clinical Cancer Research (Impact Factor: 4.43). 07/2008; 27(1):23. DOI: 10.1186/1756-9966-27-23
Source: PubMed


Heparanase is an endoglycosidase that degrades heparan sulfate, the main polysaccharide constituent of the extracellular matrix (ECM) and basement membrane. Expression of the heparanase gene is associated with the invasion and metastatic potential of a variety of tumor-derived cell types. However, the roles of heparanase in the regulation of gene expression and the subsequent cell function changes other than invasion are not clear. In the current study, we overexpressed the human heparanase gene in a human U251n glioma cell line. We found that heparanase-overexpression significantly increased cell invasion, proliferation, anchorage-independent colony formation and chemotactic migration towards fetal bovine serum (FBS)-supplied medium and stromal cell-derived factor-1 (SDF-1). These phenotypic appearances were accompanied by enhanced protein kinase B (AKT) phosphorylation. Focal adhesion kinase (FAK) and extracellular signal-regulated kinase 1 (ERK1) signaling were not altered by heparanase-overexpression. These results indicate that heparanase has pleiotropic effects on tumor cells.

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    • "Colonies of >20 cells were identified microscopically and the number of colonies/well recorded. Six replicate wells of each transfectant were included in at least three independent experiments, as published previously [13,28]. "
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    No preview · Article · Oct 2009 · Journal of Neurosurgery
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