Clonal Reconstruction and Targeting of the Correa Sequence

项目概要/摘要 现在已经确定上皮癌是在癌前病变的几十年过程中产生的。 食管腺癌是一种发病率自1950年以来上升了5倍的癌症，它始于癌前病变 称为“Barrett食管”，发展为发育不良，最后表现为恶性食管腺癌 沿着与胃腺癌的Correa序列平行的路径。病人的平均寿命 诊断为食管腺癌大约是一年，相当大的努力正在进行中，以确定其 Correa序列，特别是其癌前阶段，作为潜在的目标，阻断发病前 恶性疾病为此，我们应用了最初在我们国家开发的新型干细胞克隆技术。 实验室正常人胃肠道干细胞重建Correa序列在患者的早期 食管腺癌值得注意的是，这些患者匹配的Barrett's，异型增生和 食管腺癌产生分别产生肠化生的离散干细胞群， 发育不良（但不是肿瘤）和移植到免疫缺陷小鼠后的侵袭性腺癌。从 详细的分子遗传学分析了近100个独立的克隆，来自巴雷特，发育不良， 一个病人的腺癌病变，我们已经能够重建，在前所未有的分辨率，既直接 导致这种肿瘤的系统发育序列，以及在巴雷特和发育不良阶段识别“死端”， 并没有导致最终的肿瘤。此外，每一个克隆的干细胞巴雷特的，发育不良，腺癌， 病变代表了永久性的线，使强大的方法，以药物发现，最终导致 选择性地靶向整个Correa序列，同时保留正常的食管干细胞。在三个具体目标中，我们 将1.）克隆重建10例早期食管腺癌患者的Correa序列; 2.）建立 涉及正常食管和Correa序列干细胞的共培养物的高通量筛选用于先导发现; 和3.）开发患者匹配的正常食管和Correa序列干细胞的体内异种移植模型， 验证针对这些病变的电极导线组合。根据广泛的初步研究，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癌的演变提供基本的见解。 腺癌以及一般的上皮癌。从填补病人护理的重要空白的角度来看， 这些病变干细胞的药物发现提供了有希望的新干预措施， 食管腺癌的治疗，以及解决已经存在的疾病的治疗。

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.