芒柄花黄素通过β-catenin和p38 MAPK双靶点诱导膀胱癌细胞凋亡的分子机制研究

The bladder cancer is one of the most common cancer in Urinary system. Bladder cancer is related with multiple signaling pathways including wnt and MAPK. β-catenin and p38 play key roles in the development of bladder cancer. The isoflavone formononetin (C16H12O4) is a phytoestrogen and one of the main active components of red clover plants. Because of their structural similarity with estrogen, phytoestrogens can produce estrogenic or antiestrogenic effects. Our previous studies suggested that formononetin inactivated mitogen-activated protein kinase (MAPK) signaling pathway, which resulted in increased the expression levels of Bax mRNA and protein, and induced apoptosis in PC-3 cells. On the other hand, formononetin decreased the expression levels of β-catenin mRNA and protein and increased the expression level of p-p38 in T-24 cells. In the present study, by MTT assay, TUNEL, Hoechst, flow cytometry, Western blot, realtime-PCR, siRNA, Xenograft tumor growth, and immunohistochemistry, we identified that formononetin inhibited proliferation of bladder cancer cells and induced apoptosis via interrupting the cross-talk between MAPK signaling pathways and Akt signaling pathways. Furthermore, we focus on the effect of formononetin on the levels of β-catenin and p38 protein. Our results provide the foundation for future development of formononetin for the treatment of bladder cancer cells.

膀胱癌是泌尿系统肿瘤中最常见的肿瘤之一，Wnt和MAPK信号转导通路与其的发生发展有密切关系，β-catenin、p38分别为上述通路的关键分子，但它们的调控机制尚未明确。芒柄花黄素是传统中药三叶草的主要活性成分之一，课题组研究表明该药物能够抑制前列腺癌细胞增殖，诱导其凋亡，这可能是通过MAPK通路来实现的，并且前期实验显示芒柄花黄素可抑制膀胱癌细胞增殖，诱导其凋亡，下调膀胱癌细胞的β-catenin蛋白水平，上调p38蛋白水平。本项目拟通过体内外实验，观察药物对膀胱癌细胞作用情况，检测其抑制膀胱癌细胞增殖、诱导凋亡的作用，并通过质粒构建及转染，论证这些作用是否通过Wnt和MAPK通路，并着重检测β-catenin和p38上下游基因蛋白表达情况，探讨芒柄花黄素诱导膀胱癌细胞凋亡的分子机制，为其及同类药物防治膀胱癌提供新的靶点和理论依据。

膀胱癌是泌尿系统肿瘤中最常见的肿瘤之一，Wnt和MAPK信号转导通路与其的发生发展有密切关系，β-catenin、p38分别为上述通路的关键分子，芒柄花黄素是传统中药三叶草的主要活性成分之一，实验显示芒柄花黄素可抑制膀胱癌细胞增殖，诱导其凋亡，下调膀胱癌细胞的β-catenin蛋白水平，上调p38蛋白水平，本项目通过体内外实验，探索其抑制膀胱癌细胞增殖、诱导凋亡的作用，通过质粒构建及转染，论证这些作用是否通过Wnt和MAPK通路，并着重检测了β-catenin和p38上下游基因蛋白表达情况，探讨了芒柄花黄素诱导膀胱癌细胞凋亡的分子机制，为其及同类药物防治膀胱癌提供新的靶点和理论依据。