Inflammation and Tumor Progression: A Lesson from TNF-α-Dependent FAK Signaling in Cholangiocarcinoma
Inflammation and Tumor Progression: A Lesson from TNF-α-Dependent FAK Signaling in Cholangiocarcinoma
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DOI：
10.1007/978-1-60327-530-9_15
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发表时间：
2009-01-01
期刊：
影响因子：
--
通讯作者：
Hamaguchi, Michinari
中科院分区：
文献类型：
--
作者：
Mon, Naing Naing;Kokuryo, Toshio;Hamaguchi, Michinari
粘着斑激酶(FAK)参与了多种细胞过程，也参与了降解细胞外基质(ECM)的基质金属蛋白酶(MMPs)的产生。我们已经证明，FAK在炎性细胞因子--肿瘤坏死因子-α激活的胆管癌细胞的侵袭过程中，在基质金属蛋白酶-9的产生和随后的侵袭中起着关键作用。从本质上讲，胆管癌常与导致反复发炎的肝内胆管结石有关。由于ECM的降解是癌细胞侵袭和转移的前提步骤，我们使用明胶降解MMPs的Zymograph分析方法来阐明癌细胞基质降解系统的特征。免疫沉淀和免疫印迹分析结合位点特异性磷酸化FAK抗体显示炎症介导的肿瘤细胞中有异常的FAK活性。共聚焦免疫荧光染色不仅证实了经肿瘤坏死因子-α刺激的磷酸化FAK的定位，而且还证实了磷酸化FAK的酪氨酸含量。基底膜的破坏或穿透被认为是肿瘤细胞成功转移的关键步骤，我们使用重建到Boyden小室过滤器上的基底膜基质来检测癌细胞通过基质涂层过滤器的穿透能力。我们证明了FAK siRNA治疗在预防肿瘤侵袭方面的有效性。我们的观察提示了FAK作为恶性肿瘤治疗靶点的重要性。
Focal Adhesion Kinase (FAK) is implicated in a wide array of cellular Processes and also involved in the production of matrix metalloproteinases (MMPs) which degrade extracellular matrix (ECM). We have shown that FAK plays a critical role in MMP-9 production and subsequent invasion of the cholangiocarcinoma activated by an inflammatory cytokine, TNF-alpha. By nature, cholangiocarcinoma is frequently associated with hepatolithiasis that causes recurrent inflammation. As degradation of the ECM is a prerequisite step for the invasion and metastasis of cancer cells, we used an assay of gelatin-degrading MMPs by Zymography to clarify the characteristic feature of the matrix degrading systems of the cancer cells. Immunoprecipitation and western blot analysis together with site specific phosphorylated FAK antibodies showed aberrant FAK activity in inflammation-mediated tumor cells. Confocal immunofluorescence staining could confirm not only localization but also phosphotyrosine contents of phosphorylated FAK by TNF-alpha stimulation. Destruction or penetration of the basement membrane is thought to be an essential step in successful metastasis by tumor cells, we used a matrix of basement membrane which was reconstituted on to a filter in the Boyden Chamber and assayed the ability of cancer cells to penetrate through matrigel-coated filter. We demonstrated the effectiveness of FAK siRNA treatment to prevent tumor invasion. Our observations suggested the importance of FAK as a therapeutic target for malignant neoplasm.