Adaptable hydrogel platform to study pancreatic cancer

描述（由申请人提供）：胰腺癌是所有癌症相关死亡的第四大原因。众所周知，这种疾病很难诊断，治疗选择也非常有限。胰腺导管腺癌（PDAC）占所有类型胰腺癌的80%以上。了解PDAC细胞的生长和运动是开发有效药物治疗PDAC的关键。迄今为止，大多数体外PDAC研究都是在非自然硬化的二维（2D）组织培养塑料培养皿（TCP）上进行的。二维表面的超高刚度不仅使附着的细胞发生非自然极化，而且由于异常的机械传感导致细胞的行为不同。二维细胞培养技术在肿瘤细胞的研究中也存在不足，因为肿瘤细胞受三维（3D）肿瘤中发现的间质组织（即结缔组织，由激活的胰腺星状细胞沉积的致密细胞外基质）的高度影响。还认为，结缔组织增生与胰腺癌细胞沟通，促进肿瘤进展，阻碍药物渗透和疗效。尽管一些研究已经探索了3D基质（如Matrigel(R)）在PDAC研究中的应用，但商业上可用的基质在机械上很弱，并且包含不明确和不可控的生化成分，可能会混淆实验结果。我们的中心假设是，一个具有动态和模块化适应性的合成肿瘤生态位可以用来阐明细胞外基质（ECM）线索对PDAC细胞生长、形态发生和药物疗效的影响。为此，我们将开发合成水凝胶，该水凝胶可以在与PDAC相关的范围内通过细胞相容性光照射（365-430nm）可逆地变硬/变软。在Aim 1中，我们将开发创新的动态模拟韧带形成的水凝胶基质来封装PDAC细胞（例如，PANC-1， COLO-357和ASPC1），并研究它们的生长，形态发生和上皮-间质转化（EMT）。在目标2中，我们将独立和可逆地调节载细胞水凝胶的生物物理和生化特性，以描述各种固定化和可溶性细胞外因子对PDAC细胞命运过程的影响。我们还将揭示这些关键因素对PDAC耐药的影响。从这项研究中获得的信息将为治疗致命性PDAC开辟新的治疗选择。

DESCRIPTION (provided by applicant): Pancreatic cancer is the fourth leading cause of all cancer-related death. It is notoriously difficult to diagnose and has very limited therapeutic options. Pancreatic ductal adenocarcinoma (PDAC) accounts for more than 80% of all forms of pancreatic cancer. Understanding PDAC cell growth and motility is the key to developing effective drug therapeutics for treating PDAC. To date, most in vitro PDAC studies have been conducted on two dimensional (2D) tissue-culture plastic dishes (TCP) that are unnaturally stiff (E > 1 GPa). The ultrahigh stiffness of a 2D surface not only un-naturally polarizes the attached cells, but also causes the cells to behave differently due to abnormal mechano-sensing. 2D cell culture techniques are also inadequate in the study of tumor cells, which are highly influenced by the stromal tissues (i.e., desmoplasia, dense extracellular matrices deposited by activated pancreatic stellate cells) found in three-dimensional (3D) tumors. It is also believed that desmoplasia communicates with pancreatic cancer cells to promote tumor progression and to hinder drug penetration and efficacy. Although a few studies have explored the utility of 3D matrices, such as Matrigel(R), for PDAC research, the commercially available matrices are mechanically weak and contain ill-defined and un- controllable biochemical components that may confound the experimental results. Our central hypothesis is that a synthetic tumor niche with dynamically and modularly adaptable properties can be used to elucidate the influence of extracellular matrix (ECM) cues on the growth, morphogenesis, and drug efficacy in PDAC cells. Toward this end, we will develop synthetic hydrogels that can be reversibly stiffen/soften via cytocompatible light exposure (365-430nm) in a range relevant to PDAC. In Aim 1, we will develop innovative dynamic desmoplasia-mimetic hydrogel matrix to encapsulate PDAC cells (e.g., PANC-1, COLO-357, and ASPC1) and study their growth, morphogenesis, and epithelial-mesenchymal transition (EMT). In Aim 2, we will independently and reversibly modulate the biophysical and biochemical properties of cell-laden hydrogels in order to delineate the influence of various immobilized and soluble extracellular factors on PDAC cell fate processes. We will also reveal the influence of these critical factors on drug resistance in PDAC. The information obtained from this study will open new therapeutic options for treating the lethal PDAC.