Abstract: Objective To investigate the effect of camptothecin (CPT) on the inhibition of proliferation and induction of apoptosis of human umbilical vein endothelial cell line,ECV304,in vitro.Methods ECV304s were incubated with different concentrations of CPT.The inhibitory effect on cellular proliferation was measured by MTT assay.Cellular apoptosis was evaluated by light microscopy,electron microscopy,flow cytometry,and agarose gel electrophoresis.Results CPT could inhibit the proliferation of ECV304.The maximal inhibition rates were 67.9%,96.7%,and 97.2% at 24 h,48 h and 72 h,respectively.Having been treated with CPT,ECV304 cells were found to have typical morphologic features of apoptosis.TheResultsof agarose gel electrophoresis showed characteristic DNA ladder after ECV304 were treated with CPT.Conclusions CPT shows inhibitory effect on the proliferation of ECV304 and can induce apoptosis of ECV304.CPT may have a potential antiangiogenic effect.

Key words: Camptothecin, Apoptosis, Endothelium,vascular