Functional Imaging of Twist induced breast cancer

描述（由申请人提供）：了解肿瘤侵袭和转移提供了关于癌症进展的关键信息。为了实现这一目标，我们已经确定了一个中胚层基因，Twist，它在促进乳腺癌形成中起着至关重要的作用。该实验室的早期结果表明，MCF-7乳腺癌细胞中Twist（一种碱性螺旋-环-螺旋转录因子）的过度表达促进了肿瘤发生，并增加了异种移植物肿瘤微环境中的血管和渗透性。初步数据表明，这种转录因子的过度表达可以促进胆碱激酶的表达，胆碱激酶是与恶性转化和转移相关的标志物。此外，胆碱激酶水平增加的活性从这些转基因细胞中磷酸胆碱和含总胆碱化合物的水平升高是明显的。 目前的建议是为了了解Twist在促进乳腺癌的侵袭和转移的作用，通过使用功能成像技术改变乳腺上皮细胞的生理和生物化学。这三个具体目标是：1）通过功能性磁共振成像和光谱学使用Twist过表达乳腺癌细胞鉴定原位肿瘤中的生物化学和生理学改变，2）在乳腺癌异种移植物模型中功能性表征和成像下调Twist的作用，和3）鉴定Twist过表达细胞中的新型转移标志物并在乳腺癌患者样品中验证它们。在这项研究中，我们将使用功能性磁共振成像来识别影响乳腺肿瘤表型特征的分子变化，例如，在Twist过表达以及Twist下调细胞中，含胆碱化合物水平、乳酸水平、细胞外pH、血管体积和渗透性表面积乘积的变化。此外，我们将使用非侵入性光学成像来识别癌症进展的各个阶段，使用光学报告基因（tdTomato）转染的MCF-7/Twist细胞。最后，使用临床前模型识别的基因特征模式将应用于患者样本，以识别乳腺癌进展的潜在标志物。从长远来看，这些研究将有助于乳腺癌的病理诊断，并提供见解，有助于开发新的乳腺癌成像标记物和化疗药物。 公共卫生相关性：转移性疾病是乳腺癌死亡的主要原因。这一过程的分子表征对于开发新型诊断和治疗剂至关重要，这将减轻患者的痛苦并提高存活率。在这项研究中，我们将使用功能性磁共振成像来识别影响乳腺肿瘤表型特征的分子变化，例如，Twist过表达乳腺癌细胞中含胆碱化合物水平、乳酸水平、细胞外pH、血管体积和渗透性表面积乘积的变化。最后，将在临床前模型中使用Twist过表达乳腺癌细胞鉴定的转移进展的基因特征模式应用于患者样本，以鉴定乳腺癌进展的潜在标志物。

DESCRIPTION (provided by applicant): Understanding tumor invasion and metastasis provides crucial information with respect to carcinoma progression. Towards this goal, we have identified a mesodermal gene, Twist, which has a crucial role in promoting breast cancer formation. Earlier results from this laboratory have indicated that over-expression of Twist, a basic helix-loop-helix transcription factor, in MCF-7 breast cancer cells promotes tumorigenesis and increased vasculature and permeability within the tumor microenvironment of xenografts. Preliminary data have indicated that over-expression of this transcription factor can promote the expression of the choline kinase, a marker related to malignant transformation and metastasis. In addition, the activity of the increased levels of choline kinase is evident from the elevated levels of phosphocholine and total choline containing compounds in these transgenic cells. The present proposal is designed to understand the role of Twist in promoting breast cancer invasion and metastasis by altering the cellular physiology and biochemistry of breast epithelium by using functional imaging techniques. The three specific aims are: 1) To identify biochemical and physiological alterations in orthotopic tumors using Twist over-expressing breast cancer cells by functional magnetic resonance imaging and spectroscopy, 2) To functionally characterize and image the effects of down- regulating Twist in breast cancer xenograft models, and 3) To identify novel metastatic markers in Twist over-expressing cells and to validate them in breast cancer patient samples. In this study, we will use functional magnetic resonance imaging to identify the molecular changes that influence the phenotypic characteristics of breast tumors, such as, changes in choline containing compound levels, lactate levels, extracellular pHe, vascular volume and permeability surface area product in Twist over-expressing as well in Twist down-regulated cells. Also, we will use non-invasive optical imaging to identify various stages of cancer progression using MCF-7/Twist cells transfected with an optical reporter gene (tdTomato). Finally, the gene signature patterns identified using the preclinical model will be applied to patient samples in order to identify potential markers of breast cancer progression. In the long term, these studies will help in the pathological diagnosis of breast cancer and provide insights that will contribute to the development of novel imaging markers and chemotherapeutic drugs for breast cancer. PUBLIC HEALTH RELEVANCE: Metastatic disease is the principle cause of death from breast cancer. Molecular characterization of this process is crucial to the development of novel diagnostic and therapeutic agents that will alleviate patient suffering and increase the survival rate. In this research proposal, we will use functional magnetic resonance imaging to identify the molecular changes that influence the phenotypic characteristics of breast tumors, such as, changes in choline containing compound levels, lactate levels, extracellular pHe, vascular volume and permeability surface area product in Twist over-expressing breast cancer cells. Finally, the gene signature patterns of metastatic progression identified using Twist over-expressing breast cancer cells in preclinical model will be applied to patient samples in order to identify potential markers of breast cancer progression.