Pomegranate Seed Oil Inhibits The Malignant Behaviors Of Breast Cancer Cells

Background: Incidence of breast cancer has been rising since the late 1970 s in worldwide. Because of the high-grade malignancy,it seriously threatens the women’s health and has become a major public health problem. In the past, little is known about the anti-tumor effect of pomegranate seeds. Recently, it was found that there are some functional ingredients can inhibit cell proliferation and tumor growth of breast cancer.Objective: To analyze the fatty acid composition of pomegranate seed oil and other common oil, and to identify functional fatty acids in pomegranate seed oil. To study the effect of pomegranate seed oil on proliferation, apoptosis, migration and invasion behaviors of breast cancer cells. We analyzed the inhibition of pomegranate seed oil on breast cancer and underlying mechanism.Method: Fatty acid composition of pomegranate seed oil and other common oil was detectedby Gas Chromatography.The breast cancer cell MCF-7 and MDA-MB-231 were treated with different concentration of pomegranate seed oil for different time, cell proliferation was observed by MTT, and cell apoptosis was analyzed by flow cytometry. Also, we observed morphological changes of breast cancer cell treated with pomegranate seed oil.Then the expression of proliferation and apoptosis-related proteins were detected by Western blot, in pomegranate seed oil treated MCF-7 and MDA-MB-231 cells.The mobility and the cell number which crossed through Matrigel were detected by Wound Healing and transwell assay, in MCF-7 and MDA-MB-231 cells.After treating with pomegranate seed oil for 72 h, the expressions of MMP-2 and MMP-9 were detected by ELISA, and the expression of VEGF was detected by immunofluorescence.Result: 1. Pomegranate seed oil is mainly composed of pomegranate acid, ketone acid, linoleic acid, oleic acid, palmitic acid, stearic acid, and pomegranate acid occupied about 74.41%. 2. Compared with other common oil, only pomegranate seed oil contained pomegranate acid and ketone acid, while the proportion of palmitic acid, stearic acid, oleic acid, linoleic acid in pomegranate seed oil is lower. 3. The breast cancer cell lines of MCF-7 and MDA-MB-231 were treated with high concentrations of pomegranate seed oil. MCF-7 cell changed from the tightening state into a decentralized state; MDA-MB-231 cells changed from the long fusiform state into a round of paving stone. Both cells changed into vacuoles, karyolitic state. 4. Pomegranate seed oil could inhibit MCF-7/ MDA-MB-231 cells proliferate in dose-and time-dependent manner, compared with the control group(P< 0.05). 5. After being treated by different concentrations of pomegranate seed oil for 96 h, pomegranate seed oil could induce apoptosis(including early apoptosis,late apoptosis and dead cells) in MCF-7/MDA-MB-231 cell lines in a dose-dependent manner, compared with negative control group(P<0.05). 6. Pomegranate seed oil was shown to significantly decrease the expression levels of Cox-2 and Bcl-2, and increase the expression levels of Bax and Caspase-3(cleaved).Furthermore, it significantly upregulate the expression of p53 in MCF-7, while downregulat p53 expression in MDA-MB-231. 7. Different concentrations of pomegranate seed oil could inhibit MCF-7/ MDA-MB-231 cell migration in a dose dependent manner, after incubating for 72 h, compared with the control group(P< 0.05). 8. Different concentrations of pomegranate seed oil could inhibit MCF-7/ MDA-MB-231 cell invasiveness in a dose dependent manner, after incubating for 72 h, compared with the control group(P< 0.05). 9. Pomegranate seed oil could significantly reduce MMP-2 expression in MCF-7/MDAMB-231 cells, compared with the control group(P< 0.05). 10. Pomegranate seed oil could significantly reduce VEGF expression in MCF-7/MDAMB-231 cells, compared with the control group(P< 0.05).Conclusion: 1. Pomegranate acid is the major fatty in pomegranate seed oil, and it may be the functional fatty acids of pomegranate seed oil which can inhibit malignant behaviors in breast cancer cell. 2. The pomegranate seed oil can significantly inhibit proliferation and induce apoptosis in breast cancer cell. 3. The pomegranate seed oil inhibit proliferation and induce apoptosis in breast cancer cell, these effects were probably mediated by regulating the expression of Cox-2, Bcl-2, Bax, Caspase-3(cleaved) and p53. 4. Pomegranate seed oil can significantly inhibit the migration and invasiveness of breast cancer cell. 5. The pomegranate seed oil inhibit migration and invasion in breast cancer cell, which may probably mediated by downregulation of the expression of MMP-2 and VEGF.