黑米花色苷抑制人乳腺癌细胞促血管生成因子表达的机制

目的探讨黑米花色苷抑制HER-2/neu高表达人乳腺癌细胞株MDA-MB-453促血管生成因子表达的分子机制。方法以黑米花色苷和表皮细胞生长因子(EGF)单独或联合处理MDA-MB-453细胞株,Western blot检测HER-2/neu及MAPK信号通路关键蛋白ERK-1/-2的磷酸化水平改变,免疫荧光检测NF-κB p65的细胞内定位,RT-PCR检测肿瘤细胞促血管生成因子(包括VEGF、MMP-2/-9和uPA)在mRNA水平的表达变化。结果黑米花色苷能够显著抑制HER-2/neu和ERK-1/-2蛋白的磷酸化,阻止NF-Κb p65向细胞核内转位,并在mRNA水平抑制各促血管生成因子的表达。结论黑米花色苷可能通过对HER-2/neu及其下游EGFR/Ras/MAPK信号通路的阻断最终实现对肿瘤细胞促血管生成因子表达的抑制作用。

MECHANISMS OF BLACK RICE ANTHOCYANINS INHIBITING EXPRESSION OF ANGIOGENESIS-RELATED FACTORS IN HUMAN BREAST CANCER CELLS

Objective To illustrate the molecular mechanisms through which black rice anthocyanins inhibits the expression of tumor angiogenesis-related factors in human breast cancer cells MDA-MB-453 over-expressing HER-2/neu.Method MDA-MB-453 cells were treated by black rice anthocyanin-rich extract and/or epithelium growth factor(EGF).Western blot was then applied to verify the change of phosphorylation of HER-2/neu and ERK-1/-2.Immunoflourescence was applied to determine NF-κB p65 positioned in cells,and RT-PCR was applied to analyze the mRNA expression of tumor angiogenesis-related factors including VEGF,MMP-2/-9 and uPA.Results Black rice anthocyanin could significantly inhibit the phosphorylation level of both HER-2/neu and ERK-1/-2,prevent the transposition to nuclease of NF-κB p65,and down regulate the mRNA expression of tumor angiogenesis-related factors.Conclusion Black rice anthocyanins could inhibit the expression of tumor angiogenesis-related factors,presumably by inhibiting HER-2/neu activity and thus blocking its downstream EGFR/Ras/MAPK signaling pathway.