Xenobiotics and Breast Epithelial Cell-ECM Signaling

描述：(改编自申请者摘要)：颇具争议 存在关于外源物质与乳腺癌的关联的问题。CELL-ECM 细胞外基质)的相互作用对细胞形态至关重要，并且 细胞形态的改变改变了细胞的功能和基因转录。单元格 通过含有整合素的焦点粘连与细胞外基质相连。其他类型的 将细胞彼此连接或连接到细胞外基质的结构包括粘附剂 连接和桥粒。因为正确的问题架构和单元 形态对细胞动态平衡至关重要，我们已经研究了 外源物质干扰乳腺上皮细胞与细胞外基质的相互作用 代表人类增生性乳房疾病(PBD)模型的线条， 乳腺癌的危险因素。初步结果显示，细胞在 ECM Matrigel采用了让人联想到乳房三维形态 体内构建和对Fas介导的差异敏感性 细胞凋亡。有机氯破坏粘附性的水平和联系 与细胞间细胞外基质和细胞间通讯相关的分子。治疗 含有p，p‘-DDT的细胞相对于 对照，而Kepone则将α-连环蛋白的表达减少2倍并干扰 桥粒相对对照。这项研究的假设是 外源生物改变细胞黏附的水平、定位和联系 对局灶性粘连、桥粒和粘附物的形成至关重要的分子 连接，最终影响细胞内的信号通路(例如PI 3-激酶)、基因表达、细胞周期调控、增殖和 细胞凋亡。我们将使用有机氯(p，p‘-DDT，o，p’-DDT和Kepone)和 本提案中的非有机氯外来生物(DMBA、TPA、PhIP)。因此， 这项研究的具体目的是利用培养在 Matrigel，是：1)确定外来生物对分布的影响和 对正常细胞-细胞外基质相互作用至关重要的细胞黏附分子的结合 局灶性粘连、粘连连接或桥粒。2)检查异种生物 对PI3K/Akt信号转导的影响3)确定外来生物对人体健康的影响 细胞周期和细胞周期调节成分(pRb、E2F、P53、细胞周期蛋白和 细胞周期蛋白依赖性激酶(Cdk))。4)检查外源生物是否会改变 Fas介导的细胞凋亡。5)评估浓度的外源生物是否 与体内组织水平相关，使用 微阵列分析。这项提议的结果将提供新的 关于乳房上皮细胞中化学调节效应的信息和 人类增生性乳腺基本细胞变化的精液数据 疾病。

DESCRIPTION: (Adapted from the Applicant's Abstract): considerable controversy exists regarding the association of xenobiotics with breast cancer. Cell-ECM Extracellular Matrix) interactions are critical to cellular morphology, and alterations in cell morphology alter cell unction and gene transcription. Cells are linked to the ECM via integrin-containing focal adhesions. Other types of structures that link cells to each other or to the ECM include adherens junctions and desmosomes. Because correct issue architecture and cell morphology are critical for cellular homeostasis, we have examined whether xenobiotics disrupt cell-ECM interactions in a series of breast epithelial cell lines that represent a model of human proliferative breast disease (PBD), a risk factor for breast cancer. Preliminary results show that cells cultured on the ECM Matrigel adopt a three-dimensional morphology reminiscent of breast architecture in vivo and display differential sensitivity to Fas-mediated apoptosis. Organochlorines disrupt the levels and association of adhesion molecules associated with cell-ECM and cell-cell communication. Treatment of cells with p,p'-DDT results in increased delta-catenin levels relative to controls, whereas Kepone decreases alpha-catenin expression 2-fold and disrupts desmosomes relative to controls. The hypothesis of this research is that xenobiotics alter the levels, localization and association of cell adhesion molecules critical to the formation of focal adhesions, desmosomes and adherens junctions, which ultimately affect intracellular signaling pathways (e.g. PI 3-kinaseIAkt kinase), gene expression, cell cycle regulation, proliferation and apoptosis. We will employ organochlorine (p,p'-DDT, o,p'-DDT and Kepone) and non-organochlorine xenobiotics (DMBA, TPA, PhIP) in this proposal. Thus, the specific aims of this research, employing breast epithelial cells cultured on Matrigel, are: 1) To determine xenobiotic effects on the distribution and association of cell adhesion molecules critical to normal cell-ECM interactions and focal adhesions, adherens junctions or desmosomes. 2) To examine xenobiotic effects on PI 3-kinase/Akt signaling. 3) To determine xenobiotic effects on the cell cycle and cell cycle regulatory components (pRB, E2F, p53, cyclins and cyclin dependent kinases (cdk)). 4) To examine whether xenobiotics alter Fas-mediated apoptosis. 5) To assess whether xenobiotics at concentrations relevant to tissue levels in vivo, alter global gene expression using microarray analysis. The results of this proposal will provide novel information regarding chemical-mediated effects in breast epithelial cells and seminal data on fundamental cellular changes in human proliferative breast disease.