Mechanisms of Early Stage Mammary Tumorigenesis

早期乳腺肿瘤发生机制

• 批准号: 8349440
• 负责人: Terry van Dyke
• 金额: $ 59.63万
• 依托单位: DIVISION OF BASIC SCIENCES - NCI
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8349440
• 关键词: Acoustics; Agar; Alleles; Basement membrane; Basic Science; Beds; Breast; Breast Cancer Treatment; Breeding; Cell Membrane Permeability; Cells; Characteristics; Clinical; Collaborations; Cytokeratin; Data Storage and Retrieval; Detection; Development; Diagnosis; Diagnostic Neoplasm Staging; Disease; Duct (organ) structure; Early Diagnosis; Epithelial Cells; Eye; Genetically Engineered Mouse; Gland; Goals; Histology; Human; Image; Image Analysis; Imaging Techniques; K-18 conjugate; KRT19 gene; Keratin; Knockout Mice; Lesion; Life; Magnetic Resonance; Magnetic Resonance Imaging; Magnetism; Malignant Neoplasms; Mammary Neoplasms; Mammary Tumorigenesis; Mammary gland; Modeling; Molecular Analysis; Molecular Genetics; Mus; Noninfiltrating Intraductal Carcinoma; Pathologic; Pathway interactions; Phenotype; Pilot Projects; Predisposition; Property; Prostate; Protons; Published Comment; Regulation; Relaxation; Research; Role; Staging; Techniques; Testing; Time; Tissues; Transgenic Model; Tumor stage; Ultrasonography; Wild Type Mouse; Woman; Xenograft Model; cancer cell; cell type; density; improved; in vivo; infiltrating duct carcinoma; interest; intravital microscopy; malignant breast neoplasm; mouse model; physical property; tissue processing; tumor; tumorigenesis

There are several components to this project. Development of new imaging techniques for detection and characterization of preinvasive and early invasive mammary cancers in mice: We are developing magnetic resonance (MR) imaging, ultrasound (US) imaging, and intravital microscopy (IVM) techniques for the detection of early stage mammary cancers in mice. The purpose of developing these new imaging techniques is two-fold: (i) to perform in vivo characterization of early mammary tumorigenesis in mouse models of breast cancer (see next project below) for which imaging techniques are necessary since early stage cancers are too small to be visible by eye or palpated, and (ii) to use mouse models as a test-bed for developing new imaging strategies that can be applied in women. In addition to developing new imaging acquisition techniques, we are also developing a Mulitmodality Mouse Imaging Workstation to improve image analysis and data storage. We are currently performing a study evaluating noncontrast MR and US imaging in wild-type mice, xenograft models and transgenic models; in doing so, we have successfully developed a new strategy for performing MR/US/histology correlations using an agar grid. Upon successful completion of this pilot study, we will begin to develop US contrast-enhanced techniques for quantifying lesion vasculature in a collaboration with Paul Dayton. We have also established a collaboration with Roberto Weigert to begin IVM of the mouse mamamry glands. Investigate cell-type susceptibility in new mouse models of breast cancer: The normal human breast can be broadly characterized as being comprised of epithelial cells that express cytokeratins K18/K8 (luminal cells) and K5/K14 (basal and some epithelial cells). Some intermediate epithelial cells are known to co-express K5/K18 as well as other keratins such as K19. To determine the role of cell-type susceptibility in mammary tumorigenesis, we have developed mouse models which drive expression of a conditional T121 allele thus functionally inactivating the pRb pathway, known to be frequently altered in human breast cancer--to specific cell types under control of K18, K19 and K5 regulation (please see Project 1 for a description of these models, and crosses with prostate-specific Cre lines to drive prostate tumorigenesis). We are currently breeding these mice to mammary specific Cre lines to drive cell-type-specific, mammary-specific tumorigenesis, and have also crossed the mice to p53 conditional knockout mice to determine if the tumor phenotype can be accelerated with p53 loss. Mice with tumors will be dissected and tissues processed for pathologic and molecular analysis. We will also be applying the imaging techniques developed above to characterize the timescales of early stage tumorigenesis and progression in these different mouse models. While waiting for these mice to develop, we are performing a study of the distribution of K5, K18 and K19 cells in the normal mouse mammary gland. Quantify lesion physical properties and assess role in progression: In addition to studying the molecular and genetic characteristics of early stage tumors, we are also interested in determining the role of lesion physical properties during progression of preinvasive lesions. In general, most imaging techniques provide a direct reflection of the physcial properites of tissues: for MRI, the tissue magnetic relaxation parameters T1, T2 or proton density p; for US, their acoustic properties. Thus, the noncontrast MR and US imaging we are currently developing already provide a physical characterization. We are also interested in developing advanced techniques to quantify physical lesion properties--such as stiffness (from US elastography) and basement membrane permeability (from IVM). Such physical characteristics of lesions can be noninvasively assessed with in vivo imaging, and thus changes in these properties can be assessed over time to determine if any are predictive of progression. We will commence this project upon successful completion of the MR/US pilot study outlined above.

该项目有几个组成部分。开发用于检测和表征小鼠浸润前和早期浸润性乳腺癌的新成像技术：我们正在开发用于检测早期乳腺癌的磁共振 (MR) 成像、超声 (US) 成像和活体显微镜 (IVM) 技术在小鼠中。开发这些新成像技术的目的有两个：（i）在乳腺癌小鼠模型中对早期乳腺肿瘤发生进行体内表征（参见下面的下一个项目），由于早期癌症太小，因此需要成像技术肉眼可见或触诊，以及（ii）使用小鼠模型作为开发可应用于女性的新成像策略的试验台。除了开发新的成像采集技术外，我们还开发了多模态鼠标成像工作站，以改进图像分析和数据存储。我们目前正在进行一项研究，评估野生型小鼠、异种移植模型和转基因模型的非对比 MR 和 US 成像；在此过程中，我们成功开发了一种使用琼脂网格执行 MR/US/组织学相关性的新策略。成功完成这项试点研究后，我们将与 Paul Dayton 合作，开始开发用于量化病变脉管系统的美国对比增强技术。我们还与 Roberto Weigert 建立了合作，开始对小鼠乳腺进行 IVM。 研究新的乳腺癌小鼠模型的细胞类型易感性：正常人类乳房的广泛特征是由表达细胞角蛋白 K18/K8（管腔细胞）和 K5/K14（基底细胞和一些上皮细胞）的上皮细胞组成。已知一些中间上皮细胞共表达 K5/K18 以及其他角蛋白，例如 K19。为了确定细胞类型易感性在乳腺肿瘤发生中的作用，我们开发了小鼠模型，该模型驱动条件性 T121 等位基因的表达，从而功能性地灭活 pRb 途径，已知该途径在人类乳腺癌中经常发生改变，从而使特定细胞类型受到控制K18、K19 和 K5 调节（请参阅项目 1 了解这些模型的描述，并与前列腺特异性 Cre 系杂交以驱动前列腺肿瘤发生）。我们目前正在将这些小鼠与乳腺特异性 Cre 系进行繁殖，以驱动细胞类型特异性、乳腺特异性肿瘤的发生，并且还将这些小鼠与 p53 条件敲除小鼠进行杂交，以确定 p53 缺失是否会加速肿瘤表型。患有肿瘤的小鼠将被解剖并处理组织以进行病理和分子分析。我们还将应用上面开发的成像技术来表征这些不同小鼠模型中早期肿瘤发生和进展的时间尺度。在等待这些小鼠发育的同时，我们正在研究正常小鼠乳腺中 K5、K18 和 K19 细胞的分布。量化病变物理特性并评估在进展中的作用：除了研究早期肿瘤的分子和遗传特征外，我们还对确定病变物理特性在浸润前病变进展过程中的作用感兴趣。一般来说，大多数成像技术提供组织物理特性的直接反映：对于MRI，组织磁弛豫参数T1、T2或质子密度p；对于MRI，组织磁弛豫参数T1、T2或质子密度p；对于美国来说，是它们的声学特性。因此，我们目前正在开发的非对比磁共振和超声成像已经提供了物理表征。我们还有兴趣开发先进技术来量化物理损伤特性，例如硬度（来自美国弹性成像）和基底膜渗透性（来自 IVM）。病变的这种物理特征可以通过体内成像进行无创评估，因此可以评估这些特性随时间的变化，以确定是否有任何变化可以预测进展。我们将在成功完成上述 MR/US 试点研究后开始该项目。