Characterizing the fibrogenic role of NADPH oxidase 1 in the transition from chronic pancreatitis to pancreatic cancer

项目摘要/摘要 问题：患有慢性胰腺炎(CP)的患者患胰腺导管的风险更高 腺癌(PDAC)。CP的特征是激活的富含胰腺星状细胞(PASC)的间质， 促进了非侵袭性PAIN病变向侵袭性PDAC的发展。取得进展的关键障碍 在阻止CP向PDAC过渡的过程中，关于静止的机制的知识缺口 PASCs被炎症介质激活，扩张并合成基质和基质 金属蛋白酶(MMPs)，促进非侵袭性PAIN病变进展为侵袭性PDAC。其中 CP的炎症介质是激活PaSCs的活性氧自由基(ROS)。ROS生成 可作为NADPH氧化酶(NOx)的主要产物出现。在此之前，我们展示了Nox1信号 在CP激活的PaSCs中：i)形成纤维化组织，ii)上调转录因子E-钙粘素抑制物 Twist1和MMP9，以及III)促进胰腺癌细胞株的体外和体内侵袭。这个 目的：解决我们对Nox1/Twist1/MMP9机制的认识上的空白 CP激活的PaSCs中的信号促进了非侵袭性PAIN病变向侵袭性PDAC的进展。 中心假说：CP的诱导由PaSCs中的Nox1产生ROS，从而导致持续的 Twist1的表达。Twist1，反过来，诱导基质金属蛋白酶-9的表达，从而促进非 侵袭性Panin病变通过降解基底板转变为侵袭性PDAC。这一假设将通过以下方式进行检验 追求两个具体目标：1)在第一个目标下，我们将在体外检验抑制作用的预测 CP激活的PaSCs中的Nox1/Twist1/MMP9信号通路可抑制IV型胶原和层粘连蛋白的降解。 在第二个目标下，我们将在体内测试在CP激活的PaSCs中抑制Nox1信号的预测 通过抑制非侵袭性PAIN病变向侵袭性PDAC的降解 基膜。我们的成果将包括：1)对慢性阻塞性肺疾病进展机制的新认识， 2)对NOX1相关的PDAC进展机制的新认识；3)高影响力的研究经验 对本科生来说。这种方法是创新的，因为它将评估一代人在多大程度上 CP激活的PaSCs中Nox1来源的ROS可以促进非侵袭性PanIN病变的进展 侵入性PDAC。这项拟议的研究意义重大，因为一项发现，CP-1中Nox1的缺乏激活了 PaSCs通过抑制基底膜的降解来阻止Panin病变向侵袭性PDAC的进展 LIMANA将为未来针对开发Rational的翻译研究奠定可行性和前提， 间质靶向治疗 早期阶段 PDAC(例如， 原位癌) 这一点，与其他 方法可能会导致临床策略，以提高患者的存活率。此外，这些研究是 旨在促进本科生多元化参与的机会，为他们提供 接触动手实验和密切指导。

PROJECT SUMMARY/ABSTRACT The problem: Patients suffering from chronic pancreatitis (CP) have a higher risk of pancreatic ductal adenocarcinoma (PDAC). CP is characterized by an activated pancreatic stellate cell (PaSC)-rich stroma, which has facilitated the progression of non-invasive PanIN lesions to invasive PDAC. A critical barrier to progress in preventing the CP-to-PDAC transition is the gap of knowledge regarding the mechanism by which quiescent PaSCs become activated by inflammatory mediators, expand, and synthesize stroma and matrix metalloproteinases (MMPs), facilitating the progression of non-invasive PanIN lesions to invasive PDAC. Among the inflammatory mediators of CP are reactive oxygen species (ROS), which activate PaSCs. ROS generation can occur as a primary product of NADPH oxidase (Nox) enzymes. Previously, we showed that Nox1 signaling in CP-activated PaSCs: i) forms fibrotic tissue, ii) up-regulates both the transcription factor E-cadherin repressor Twist1 and MMP-9, and iii) facilitates the invasion of pancreatic cancer cell lines both in vitro and in vivo. The objective: To address the gaps in our knowledge regarding the mechanisms by which Nox1/Twist1/MMP-9 signaling in CP-activated PaSCs facilitates the progression of non-invasive PanIN lesions to invasive PDAC. The central hypothesis: The induction of CP generates ROS by Nox1 in PaSCs, which lead to a sustained expression of Twist1. Twist1, in turn, induces the expression of MMP-9, which promotes the progression of non- invasive PanIN lesions to invasive PDAC by degrading the basal lamina. The hypothesis will be tested by pursuing two specific aims: 1) Under the first aim, we will test in vitro the prediction that inhibiting Nox1/Twist1/MMP-9 signaling in CP-activated PaSCs attenuates the degradation of collagen IV and laminin. Under the second aim, we will test in vivo the prediction that inhibiting Nox1 signaling in CP-activated PaSCs prevents the progression of non-invasive PanIN lesions to invasive PDAC by attenuating the degradation of basal lamina. Our outcomes will include 1) new knowledge of CP-related mechanisms of progression of PDAC, 2) new knowledge of Nox1-related mechanisms of progression of PDAC, 3) high impact research experiences for undergraduate students. The approach is innovate because it will assess the extent to which the generation of Nox1-derived ROS from CP-activated PaSCs can facilitate the progression of non-invasive PanIN lesions to invasive PDAC. The proposed research is significant because a finding that the lack of Nox1 in CP-activated PaSCs prevents the progression of PanIN lesions to invasive PDAC by attenuating the degradation of basal lamina will establish the feasibility and premise for future translational research directed at developing rational, stroma-targeted therapies of early-stages of PDAC (e.g., carcinoma in situ) that, in combination with other approaches might lead to clinical strategies to increase the survival of patients. Moreover, these studies are designed to promote opportunities for a diverse undergraduate student participation providing them with exposure to hands-on experiments and close mentoring.