Angiostatin upregulates E-selectin in proliferating endothelial cells

Area of Science:

• Endothelial biology
• Molecular medicine
• Cancer research

Background:

• Angiostatin, a plasminogen fragment, inhibits angiogenesis.
• The impact of angiostatin on endothelial gene expression remains largely unknown.

Purpose of the Study:

• To investigate the effect of angiostatin on endothelial gene expression, specifically E-selectin.
• To understand the mechanism of angiostatin's anti-angiogenic activity.

Main Methods:

• Treatment of bovine capillary endothelial cells with recombinant angiostatin.
• Analysis of E-selectin and P-selectin polypeptide levels.
• Assessment of E-selectin mRNA and cell adhesion activity.
• Evaluation of cell cycle progression.

Main Results:

• Angiostatin significantly increased E-selectin polypeptide and mRNA levels in proliferating endothelial cells.
• E-selectin function (adhesion activity) was also enhanced by angiostatin in proliferating cells.
• Angiostatin did not significantly affect P-selectin levels or endothelial cell cycle progression.

Conclusions:

• Angiostatin selectively upregulates E-selectin in proliferating endothelial cells in vitro.
• This selective upregulation may be a key mechanism for angiostatin's tumor growth inhibition.
• The findings suggest angiostatin spares quiescent endothelium, potentially reducing side effects.