Luminacins: a family of capillary tube formation inhibitors from Streptomyces sp. II. Biological activities.

Twelve of the fourteen isolated components of the luminacin family were assayed for activity to inhibit capillary tube formation in vitro. Seven of them showed potent activity with IC50 values of less than 0.1 microg/ml in a rat aorta matrix culture model. Luminacin D, the strongest inhibitor, inhibited both endothelial cell proliferation and capillary tube formation. Morphological observation suggested that luminacin D inhibited the rearrangement of endothelial cells in the initial stage of tube formation. Luminacins and their derivatives are good candidates for application as angiogenesis inhibitors with a novel mechanism of action.