Clonal Reconstruction and Targeting of the Correa Sequence

项目概要/摘要 现在已经明确，上皮癌是在癌前病变的数十年过程中产生的。 食管腺癌是一种癌症，自 1950 年以来发病率增加了 5 倍，始于癌前病变 被称为“巴雷特食管”，进展为不典型增生，最后发展为恶性食管腺癌 沿着与胃腺癌科雷亚序列平行的路径。随着患者的平均预期寿命 诊断为食管腺癌大约需要一年的时间，目前正在进行大量努力来定义其 科雷亚序列，特别是其恶变前阶段，作为在疾病发作之前拦截的潜在目标 恶性疾病。为此，我们应用了最初在我们的实验室开发的新型干细胞克隆技术。 正常人胃肠道干细胞实验室重建早期胃肠道患者的 Correa 序列 食管腺癌。值得注意的是，这些患者匹配的 Barrett 病、不典型增生和 食管腺癌产生离散的干细胞群，分别产生肠化生， 发育不良（但不是肿瘤），以及移植到免疫缺陷小鼠后的侵袭性腺癌。来自一个 对来自 Barrett 氏症、发育异常和 一名患者的腺癌病变，我们已经能够以前所未有的分辨率重建直接 导致这种肿瘤的系统发育序列，以及识别巴雷特和发育不良阶段的“死胡同” 对最终的肿瘤没有贡献。而且，巴雷特氏病、不典型增生和腺癌的克隆干细胞 病变代表永久的细胞系，这些永久的细胞系使强大的药物发现方法成为可能，并最终取得了领先地位 选择性地靶向整个 Correa 序列，同时保留正常的食管干细胞。为了实现三个具体目标，我们 将 1.) 从 10 名早期食管腺癌患者中克隆重建 Correa 序列； 2.) 建立 高通量筛选，涉及正常食管和 Correa 序列干细胞的共培养，以发现先导化合物； 3.) 开发患者匹配的正常食管干细胞和 Correa 序列干细胞的体内异种移植模型 验证针对这些病变的先导组合。基于广泛的初步研究，我们预计分析 这些进行性病变的患者匹配干细胞将为食管进化提供基本见解 腺癌和一般上皮癌。从填补患者护理方面的重要空白的角度来看， 这些病变干细胞组实现的药物发现为预防发病提供了有前景的新颖干预措施 食管腺癌的治疗以及治疗已经发生的疾病的治疗。

PROJECT SUMMARY/ABSTRACT It is now well established that epithelial cancers arise in a multi-decade process from precancerous lesions. Esophageal adenocarcinoma, a cancer whose incidence has risen 5-fold since 1950, initiates with precancerous lesions known as “Barrett's esophagus”, progresses to dysplasia, and finally emerges as malignant esophageal adenocarcinoma along a path that parallels the Correa Sequence for gastric adenocarcinoma. As the average life expectancy of patients diagnosed with esophageal adenocarcinoma is approximately one-year, considerable efforts are underway to define its Correa sequence, and especially its pre-malignant stages, as potential targets for interdiction ahead of the onset of malignant disease. Toward this end, we have applied novel stem cell cloning technologies originally developed in our laboratories for normal human gastrointestinal tract stem cells to reconstructing the Correa sequence in patients with early esophageal adenocarcinoma. Significantly, each of these patient-matched endoscopic biopsies of Barrett's, dysplasia, and esophageal adenocarcinoma yields discrete populations of stem cells that respectively yield intestinal metaplasia, dysplasia (but not tumors), and aggressive adenocarcinoma following transplantation to immunodeficient mice. From a detailed molecular genetics analysis of nearly 100 independent clones from across the Barrett's, dysplasia, and adenocarcinoma lesions of one patient, we have been able to reconstruct, at unprecedented resolution, both the direct phylogenetic sequence that led to this tumor as well as identify “dead-ends” at both the Barrett's and dysplasia stages that did not contribute to the final tumor. Moreover, each of the cloned stem cells of Barrett's, dysplasia, and adenocarcinoma lesions represent permanent lines that have enabled powerful approaches to drug discovery that has culminated in leads that selectively target the entire Correa sequence while sparing normal esophageal stem cells. In three specific aims, we will 1.) clonally reconstruct the Correa sequence from 10 patients with early esophageal adenocarcinoma; 2.) establish high-throughput screens involving co-cultures of normal esophageal and Correa sequence stem cells for lead discovery; and 3.) develop in vivo xenograft models of patient-matched normal esophageal and Correa sequence stem cells for validating lead combinations targeting these lesions. Based on extensive preliminary studies, we anticipate the analysis of patient-matched stem cells of these progressive lesions will provide fundamental insights into the evolution of esophageal adenocarcinoma and as well as epithelial cancers in general. From the standpoint of filling important gaps in patient care, the drug discovery enabled by these sets of lesional stem cells offers promising and novel interventions to prevent to onset of esophageal adenocarcinoma as well as ones to address disease that has already taken hold.