A Vascularized, In Vitro, Organotropic Metastasis Model to Generate Dormant Micrometastases

项目摘要/摘要 转移是癌症相关死亡的90%的原因，这表明需要有针对性的新疗法 特别是为了防止和/或消除转移。起源于乳腺肿瘤的细胞显示出不同的 器官亲和性转移模式，并专门针对肺、脑或骨进行磨练。一旦远处的组织被渗透， 这些细胞通常休眠很多年，甚至几十年，然后恢复活跃的增殖状态。 这些由单个细胞或小细胞团组成的休眠微转移瘤对 传统的化疗只能有效地治疗活跃的增殖细胞。而动物模型则有 传统上用于治疗性筛选，体内成像方式的分辨率限制使其 难以量化旨在防止渗出或消除渗出的新疗法的有效性 潜伏的微转移瘤。为了绕过这一限制，我们建议在体外生成血管化的 转移模型诱导器质性外渗和形成潜伏性转移。我们将利用我们的 在生物化学和机械可调合成水凝胶结构的开发方面的专业知识 产生组织特异性环境，允许癌细胞通过外渗渗透，并诱导 渗出的细胞处于休眠状态。我们最近开发了一种基于图像引导的激光水凝胶 一种退化技术，允许制造准确概括 体外体内血管系统的复杂、致密的结构。我们将把这项新技术与我们的 在制造工程化微环境以生成3D血管化体外模型方面的专业知识 由器官特有的微组织组成，这些组织概括了生化、机械和血液动力学 脑、肺和骨组织的特性，以产生器质性乳腺癌模型，诱导 对癌细胞的浸润性休眠。通过这一资助机制，我们将组织我们的研究来实现 以下目标：(1)产生器官特异性组织结构，概括机械、化学、 以及脑、肺和骨组织的血流动力学特性，允许渗透和诱导休眠 高转移性癌细胞，(Ii)表现出诱导乳腺癌器质性外渗的能力 具有已知基因特征的细胞可以诱导特定的脑、肺或骨转移，以及(Iii)证明 定量监测渗出、渗透和休眠的能力。这个用来模拟器官的体外装置- 休眠转移瘤的特定形成可以为环境机制提供重要的洞察。 控制器官亲和性转移，形成休眠转移，并帮助发展新的 专门针对阻止渗出或消除潜伏性微转移的治疗方法。

PROJECT SUMMARY/ABSTRACT Metastasis is responsible for 90% of cancer associated mortality indicating the need for new therapies targeted specifically toward preventing and/or eliminating metastasis. Cells originating from breast tumors display distinct organotropic metastasis patterns and hone specifically to lung, brain, or bone. Once a distant tissue is infiltrated, these cells often lay dormant for many years, or even decades, before reverting to an actively proliferating state. These dormant micrometastases composed of single cells, or small cell clusters, are highly resistant to conventional chemotherapies that only effectively treat actively proliferating cells. While animal models have traditionally been used for therapeutic screening, resolution limitations of in vivo imaging modalities make it difficult to quantify the effectiveness of new therapies targeted toward preventing extravasation or eliminating dormant micrometastases. To circumvent this limitation, we propose the generation of a vascularized in vitro metastasis model to induce organotropic extravasation and formation of dormant metastases. We will utilize our expertise in the development of biochemically and mechanically tunable synthetic hydrogel constructs to generate tissue-specific environments that allow for cancer cell infiltration via extravasation and that induce a dormant state in extravasated cells. We have recently developed an image-guided, laser-based hydrogel degradation technique that allows for fabrication of 3D microfluidic networks that accurately recapitulate the complex, dense architecture of in vivo vasculature in vitro. We will combine this new technology with our expertise in the fabrication of engineered microenvironments to generate a 3D vascularized in vitro model composed of organ-specific microtissues that recapitulate the biochemical, mechanical, and hemodynamic properties of brain, lung, and bone tissue to generate an organotropic breast cancer model that induces dormancy upon cancer cell infiltration. Through this funding mechanism we will organize our research to achieve the following objectives: (i) generate organ-specific tissue constructs that recapitulate the mechanical, chemical, and hemodynamic properties of brain, lung, and bone tissue that allow for infiltration and induce dormancy in highly metastatic cancer cells, (ii) demonstrate the ability to induce organotropic extravasation of breast cancer cells with genetic signatures known to induce metastasis specifically to brain, lung, or bone, and (iii) demonstrate the ability to quantitatively monitor extravasation, infiltration, and dormancy. This in vitro device to model organ- specific formation of dormant metastases could provide significant insight into the environmental mechanisms that govern organotropic metastasis, formation of dormant metastases, and aid the development of new therapeutics targeted specifically toward halting extravasation or eliminating dormant micrometastases.