RESUMO
Aim To investigate the inhibitory effect of paeonol (Pae) on the human esophageal cancer cell line Eca-109 in vitro and in vivo and its effect on apoptosis.Methods Cytotoxic effect of Pae on Eca-109 cells cultured in vitro was measured by MTT assay.Anti-tumor activity was performed on BALB/c nude mice xenografts model.The morphologic changes of tumor tissue were observed under light microscope and transmission electron microscope.The apoptosis index was assessed by TUNEL.Results Pae had significant in- hibitory effect on the proliferation of Eca-109 cells,and the IC50 value was 0.342 mmol?L-1.In the model of human esophageal cancer xenografts in BALB/c nude mice,the inhibitory rates of Pae group (25、50、100、200 mg?kg-1) were 10.67%、23.54%、27.91% and 34.46% respectively.In vivo administration of Pae 100 mg?kg-1 combined with cisplatin 5 mg?kg-1 resulted in a significant inhibition of Eca-109 tumor growth with the inhibitory rate of 77.91%,compared with cisplatin used alone (58.71%).The more apoptotic tumor cells could be seen under light microscope in every theraperutic groups than those in control.Changes of ultrastructure of tumor cells including concentration and side accumulation of the nuclear chromatin,and the fragmentation of the nuclear was observed under transmission electronic microscope.Apoptosis body was also found.The apoptosis indexes of every theraperutic groups were significantly different from the control.Conclusion Pae can inhibit the cell growth and induce apoptosis in human esophageal cancer cell line Eca-109 in vitro and in vivo.