Can we identify novel angiogenesis inhibitors from cultured embryonic cells?

The first vascular structures in embryos are formed by vasculogensis, the de novo formation of blood vessels from angioblasts. However, angiogenesis, the sprouting of capillaries from pre-existing blood vessels, are also involved in the development of embryonic vascular system in certain organs, such as the kidney or the brain. These facts led us to speculate that embryonic tissues could produce potent angiogenesis inhibitors as well to refine the primitive vascular development. In the present study, we found that two different types of cultured human embryonic cells, 293T and WI-38, produced soluble factors that completely inhibited angiogenic effects of vascular endothelial growth factor on microvascular endothelial cells. Since angiogenesis is related to various pathological states, including tumor growth and metastasis and diabetic retinopathy, to identify novel potent angiogenesis inhibitors from cultured embryonic cells by differential display techniques or DNA microarray technology might be a valuable strategy to develop a novel therapeutic approach.