Fucoidan On Human Breast Cancer Mcf-7 Cell Proliferation And Apoptosis

Objective To investigate the effects and related mechanism of fucoidan on the proliferation and apoptosis in breast carcinoma cell line MCF-7.Methods Cultured MCF-7 cells were divided into control and treated groups with different concentrations of fucoidan (100mg/L,300 mg/L,500 mg/L,1000 mg/L) .After being treated by fucoidan for 48 hours,MTT assay was used to detect the inhibitory rate of MCF-7 cells proliferation,cells were observed in apoptosis dyed by Hoechst 33258 with a fluorescence microscope and agarose gel electrophoresis. The changes of bcl-2 and bax gene expression in both fucoidan treatment groups and control group were measured by RT-PCR and Western blotting.Results Fucoidan with different experimental concentrations effectively inhibited the proliferation of MCF-7 cells (P<0.01) .Apoptosis bodies were observed in stained cells by Hoechst 33258 under a fluorescence microscope. Inhibition ratio and apoptosis rate increased in a concentration dependent manner. Agarose gel eletrophoresis of DNA revealed the apoptosis characteristic"ladder"pattern in fucoidan effected groups of 300 mg/L,500 mg/L and 1000 mg/L. Fucoidan down-regulated the expression of bcl-2 and up-regulated bax in the level of mRNA and protein. The ratio of bcl-2 to bax decreased as the fucoidan concentrations increased (P<0.05) .Conclusions Fucoidan inhibits the cell proliferation and induces cell apoptosis in a concentration dependent manner,the apoptosis is related to the down-regulation of anti-apoptotic gene bcl-2 and up-regulation of apoptotic gene bax. Fucoidan may become a potential halobiotic antitumor drug.