Engineered Microenvironments to model effect of size in tumor progression

描述（由申请人提供）：本提案的目的是模拟肿瘤大小和生长在促进肿瘤进展中的作用。更具体地说，该提案旨在创建一个微制造平台，该平台将允许以高通量方式生成均匀的、尺寸受控的微肿瘤，并研究肿瘤微环境、细胞-细胞相互作用和转录因子中的尺寸依赖性差异。近年来，肿瘤微环境被认为是肿瘤发生和发展的重要因素，导致肿瘤转移，这是癌症相关死亡的主要原因。肿瘤微环境由肿瘤细胞、基质细胞、细胞外基质和非细胞成分组成，包括缺氧、间质压力和代谢应激。生长的肿瘤对周围细胞和上皮施加力，产生径向和周向应力。肿瘤生长还导致代谢应激、缺氧、坏死、增加的基质硬度和间质液压力。虽然肿瘤大小被认为是转移和患者生存的重要预测因素之一，但肿瘤大小与临床结局（转移、死亡率）之间的机制联系尚未得到充分理解。在乳腺癌患者中，这种情况因淋巴结和激素受体状态而复杂化。该提案旨在1）开发三维（3D）微制造平台，以使用亚型特异性乳腺癌细胞系产生具有受控微环境的尺寸受控的微肿瘤，以及2）了解肿瘤大小对微环境的影响，并描绘肿瘤大小促进肿瘤发生和转移的机制。目标1将使用微加工技术在非粘附性水凝胶微威尔斯孔中形成细胞图案，并产生不同大小的尺寸受控的微肿瘤。各种亚型特异性细胞系（管腔、基底、三阴性等）将用于研究它们生长动力学中的尺寸依赖性差异， 激素状态、细胞-细胞相互作用和肿瘤微环境。在目标2中，将研究微小肿瘤中的大小依赖性转录变化，并将使用RNA干扰和小分子抑制剂进一步了解肿瘤大小相关肿瘤进展背后的机制。 所提出的方法是新颖的，简单的和廉价的，并将允许以高通量的方式制造3D微肿瘤模型。以尺寸依赖性方式控制微环境的能力将有助于发现参与调节肿瘤细胞中形态和转录变化的关键信号传导机制。这种方法可以潜在地用作更相关的3D药物筛选平台，以取代当前的2D细胞单层。

DESCRIPTION (provided by applicant): The objective of this proposal is to model the effect of tumor size and growth in promoting tumor progression. More specifically, the proposal aims to create a micro fabricated platform that will allow generation of uniform, size-controlled micro tumors in a high throughput manner and study size-dependent differences in tumor microenvironment, cell-cell interaction and transcription factors. Recently tumor microenvironment has been considered as an important player in tumorigenesis and progression leading to metastasis, a major cause of cancer-related mortality. Tumor microenvironment consists of tumor & stromal cells, extracellular matrix and non-cellular components that include hypoxia, interstitial pressure and metabolic stresses. Growing tumor exerts forces on the surrounding cells and epithelium creating radial and circumferential stress. Tumor growth also results in metabolic stress, hypoxia, necrosis, increased matrix stiffness and interstitial fluid pressure. Although tumor size has been considered as one of the important predictor of metastasis and patient survival, the mechanistic link between tumor size and the clinical outcome (metastasis, mortality) is not well understood. In breast cancer patients, this scenario is complicated by nodal and hormonal receptor status. This proposal aims 1) to develop three-dimensional (3D) micro fabricated platform to generate size-controlled micro tumors with controlled microenvironments using sub-type specific breast cancer cell lines and 2) to understand the effect of tumor size on microenvironment and delineate the mechanism by which tumor size promotes tumorigenesis and metastasis. Aim 1 will use micro fabrication technologies to pattern cells in non-adhesive hydrogel micro wells and generate size-controlled micro tumors of different sizes. Various sub-type specific cell lines (luminal, basal, triple negative etc.) will be used to investigate the size-dependent differences in their growth kinetics, hormonal status, cell-cell interaction and tumor microenvironment. In Aim 2, size-dependent transcriptional changes in micro tumors will be studied and this information will be used further to understand the mechanism behind tumor size-related tumor progression using RNA interference and small molecule inhibitors. The proposed approach is novel, easy and inexpensive and will allow fabricating 3D micro tumor models in a high throughput manner. Ability to control microenvironments in size-dependent manner will facilitate discovery of key signaling mechanisms involved in the regulation of morphological and transcriptional changes in tumor cells. This approach can potentially be used as a more relevant 3D drug screening platform to replace current 2D cell monolayers.