Elucidation and targeting of paracrine cascades in PDAC

摘要 胰腺导管腺癌（PDAC）是最致命的恶性肿瘤之一，这主要是因为它们缺乏 对目前的细胞毒性、靶向和免疫疗法的反应。PDAC肿瘤组织具有广泛的， 促结缔组织增生基质，其既抑制血管生成又限制灌注和扩散。因此，委员会认为， 通过全身给药的治疗剂的递送受到阻碍，降低了药物功效， 增加全身毒性。事实上，PDAC基质的多种组分支持其存活和生长， 例如通过调节促进肿瘤存活的局部免疫抑制微环境。 相反，我们以前表明，至少有一些元素的肿瘤间质抑制PDAC的生长， 进展，例如Hedgehog通路响应性肌成纤维细胞。调节PDAC的早期尝试 基质，以促进药物输送失败后，临床翻译。临床后试验最终 表明，抑制个别途径后的基质再调节可导致不可预测的 多个额外的细胞类型的后果。基于这些数据，我们假设个体旁分泌 通路通常连接在一起形成“旁分泌级联”，其通过多个通路传播， 细胞类型。我们提出，重建这些旁分泌级联提供了机会， 了解治疗干预的后果，并推断作用于患者的候选靶点。 PDAC TME内广泛的细胞类型以实施基质再调节。 为了测试这一点，我们将利用一系列创新的系统生物学工具， 我们的跨学科团队其中包括一套利用监管计算领域的算法， 网络分析，以及用于研究单细胞数据集结果的技术创新技术。 此外，我们将从我们的多学科临床研究小组成员收集的样本中获得独特的数据集。 在纽约长老会医院胰腺中心的服务。其中包括获取人类PDAC 肿瘤间质液，并产生匹配的肿瘤、正常胰腺、脾脏和血液样品组， PDAC患者我们还将常规地利用新鲜的PDAC组织样本，使肿瘤“外植体”成为一种新的表达方法。 用于PDAC的短期、中等通量研究的体内模型系统。这一新的模型系统使 以不可能通过研究完整肿瘤的方式解剖复杂的多细胞表型， 纯化细胞类型的共培养物 利用这些方法，我们将重建PDAC中的旁分泌级联网络，并进行验证 实验性地选择候选人。我们还将测试通过研究发现的特定候选途径， 连接肌成纤维细胞与髓源性抑制细胞和细胞毒性淋巴细胞的Hh通路。 我们希望这些研究能为PDAC中旁分泌串扰的研究提供更广泛的理解 并且还为PSRC联合体提供多种有价值的资源和技术。

Abstract Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal malignancies due largely to their lack of response to current cytotoxic, targeted, and immune therapies. PDAC tumor tissues harbor an expansive, desmoplastic stroma that both suppresses angiogenesis and limits perfusion and diffusion. Consequently, delivery of therapeutic agents through systemic administration is impeded, lowering drug efficacy and increasing general toxicity. Indeed, multiple components of the PDAC stroma support its survival and growth, for example by conditioning a locally immunosuppressed microenvironment that facilitates tumor survival. Conversely, we previously showed that at least some elements of the tumor stromal restrain PDAC growth and progression, for example Hedgehog pathway-responsive myofibroblasts. Early attempts to modulate the PDAC stroma in order to facilitate drug delivery failed upon clinical translation. Post-clinical trials ultimately demonstrated that stromal remodulation upon inhibition of individual pathways can lead to unpredictable consequences in multiple additional cell types. Based on these data, we hypothesize that individual paracrine pathways typically link together to form “paracrine cascades” that propagate through multiple pathways and cell types. We advance that reconstructing these paracrine cascades offers both the opportunity to better understand the consequences of therapeutic intervention and also to infer candidate targets that act on a broad range of cell types within the PDAC TME to enact stromal remodulation. In order to test this, we will make use of a series of innovative systems biology tools built by members of our transdisciplinary team. These include a suite of algorithms leveraging the computational field of regulatory network analysis, as well as technically innovative techniques for studying outcomes in single cell datasets. Moreover, we will acquire unique dataset from samples collected by members of our multidisciplinary clinical service at the Pancreas Center of New York Presbyterian Hospital. These include acquiring human PDAC tumor interstitial fluid and generating matched sets of tumor, normal pancreas, spleen, and blood samples from PDAC patients. We will also routinely utilize fresh PDAC tissue samples to make tumor “explants” a novel ex vivo model system for the short-term, medium throughput study of PDAC. This new model system enables the dissection of complex multi-cellular phenotypes in ways that are not possible through study of intact tumors or co-cultures of purified cell types Using these approaches, we will reconstruct the network of paracrine cascades in PDAC and validate selected candidates experimentally. We will also test a specific candidate pathway uncovered through study of the Hh pathway that connects myofibroblasts to myeloid derived suppressor cells and cytotoxic lymphocytes. We expect that the proposed studies will provide an expansive understanding of paracrine crosstalk in PDAC and also provide multiple valuable resources and techniques to the PSRC consortium.