DIETARY SOY ISOFLAVONES AND PROSTATE CANCER PROGRESSION

本提案的目的是调查 大豆异黄酮在前列腺癌（PCA）进展和血管生成中的作用。的 具体目标是：l）研究大豆异黄酮对 PCA抑制膜型金属蛋白酶（MT-MMP）表达 细胞、成纤维细胞或内皮细胞（EC），和2） 确定是否含有大豆分离蛋白（SPI）或纯化的 前列腺酮抑制前列腺肿瘤进展、血管生成和MT-MMP 体内表达。人PCA细胞（PC-3、DU 145和LNCAP）， 成纤维细胞和EC将用异黄酮处理。含MMP 制备条件培养基和含MT-MMP的质膜。 将应用RNA酶保护试验、蛋白质印迹法和酶谱法 检测MT-MMP的mRNA、蛋白和活性，以验证假设 前列腺素能抑制PCA的进展， 通过抑制PCA和成纤维细胞以及EC的MT-MMP表达， 分别在动物研究中，将人PCA细胞接种裸鼠， 喂食对照、基于SPI的或补充孕酮的饮食。肿瘤大小将 检测肿瘤组织中MT-MMP mRNA、蛋白表达， 和活性，以评价马槟榔酮对体内抑制的作用 PCA进展。抗血管生成的作用将是 通过微血管的免疫组织化学分析进行评价。

The objective of this proposal is to investigate the preventive role of soy isoflavones in prostate cancer (PCA) progression and angiogenesis. The specific aims are: l) to study the effects of soy isoflavones on inhibiting expression of membrane-type metalloproteinase (MT-MMP) by PCA cells, fibroblasts, or endothelial cells (ECs) in vitro, and 2) to determine if diets containing soy protein isolate (SPI) or purified isoflavones inhibit prostate tumor progression, angiogenesis, and MT-MMP expression in vivo. Human PCA cells (PC-3, DU 145, and LNCAP), fibroblasts, and ECs will be treated with isoflavones. MMPs-containing conditioned media and MT-MMP-containing plasma membranes will be prepared. RNase protection assays, Western blotting, and zymography will be applied to determine mRNA, protein, and activity of MT-MMP to test the hypothesis that isoflavones inhibit PCA progression, and prostate tumor angiogenesis by inhibiting MT-MMP expression by PCA and fibroblasts, and ECs, respectively. In animal study, human PCA cell-inoculated nude mice will be fed control, SPI-based, or isoflavone-supplemented diets. Tumor sizes will be measured, and tumors removed for determinations of MT-MMP mRNA, protein and activity to evaluate the effects of isoflavones on in vivo inhibition of PCA progression. Anti-angiogenic effect of isoflavones will be evaluated by immunohistochemical analysis of microvessels.