Abstract: BACKGROUND ＆ AIM: To investigate the inhibition of grape proanthocyanidins(GPC) on MMP-2 protein of breast cancer tissue. MATERIAL AND METHODS: Forty famale BALB/c mice inoculated with EMT-6 breast cancer cells were divided into tumor-control group and 10、100 and 200mg/kg GPC groups. GPC experimental groups were given different dose of GPC by mouth once a day for two weeks.Mice in control group were given equal amount of nomal salt solution only.MMP-2 protein in tumor tissues was assessed by Western blot and immunohistochemistry .The proliferation of cancer cells were evaluated by MTT assay, and the weights of the tumor in each group were compared also. RESULTS: 100、200 mg/kg GPC could inhibit the expression of MMP-2 protein and the proliferation of breast cancer cells. The expression of MMP-2 protein in the 100、 200 mg/kg GPC groups were 0.73±0.04 and 0.69±0.04 respectively, by western bolt and the proliferation of cancer cells were 0.81±0.21 and 0.71±0.11 respectively, by MTT assay . Compared with the control group, the differences were significanly(P<0.05). There was no difference between 10 mg/kg GPC group and the tumor control group.CONCLUSION: GPC could inhibit the expression of MMP-2 protein and proliferation of breast cancer cells.

Key words: grape proanthocyanidins;breast neoplasms, matrix metalloproteinase-2