Objectives To investigate whether apoptosis can be induced by Octreotide in human hepatoma cells in vitro and elucidate the antineoplastic mechanism of Octreotide in hepatoma.Methods A cultured human hepatoma cell line,BEL-7402,was exposed to Octreotide and apoptosis was evaluated by cytochemical staining(Hochesst 33258),transmission electron microscopy,agarose gel electrophoresis and flow cytometry(FCM).Results After exposure to 0.2 μg/ml Octreotide,apoptosis with nuclear chromatin condensation as well as fragmentation,cell shrinkage and the formation of apoptotic bodies was observed using cytochemical staining and transmission electron microscopy.A DNA ladder in agarose gel electrophoresis was also displayed.FCM showed that the apoptotic cell number rose with an increase in the concentration of Octreotide(0- 2 iμg/ml).There was a positive correlation between Octreotide concentration and apoptotic rate in BEL-7402 cells(r=0.809,P<0.05).Conclusion Apoptosis in human hepatoma cells can be induced by Octreotide,which may be related to the mechanism of antineoplastic action of Octreotide in hepatoma.