Epithelial mesenchymal transition in gastrointestinal homeostasis and disease

胃肠道稳态和疾病中的上皮间质转化

• 批准号: 9110246
• 负责人: Seema Khurana
• 金额: $ 32.73万
• 依托单位: UNIVERSITY OF HOUSTON
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-18 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9110246
• 关键词: Actin-Binding Protein; Actins; Adult; ApcMin/+ mice; Apoptosis; BRCA1 gene; Biochemical; Biological; Biological Assay; Cancer Patient; Cell Nucleus; Cells; Chronic Kidney Failure; Clinical; Clinical Trials; Colon; Colon Carcinoma; Colonic Neoplasms; Colorectal; Colorectal Cancer; Complex; Complication; Crohn' s disease; Cytoskeleton; Development; Diabetic Nephropathy; Diagnosis; Disseminated Malignant Neoplasm; Drug resistance; End stage renal failure; Enrollment; Epidermal Growth Factor Receptor; Epithelial; Epithelial Cells; Esophageal; Event; Fibrosis; Gastrointestinal Diseases; Gene Expression; Generations; Genitourinary system; Goals; Health; Human; Immunosuppression; Intestines; Knockout Mice; Link; Malignant Neoplasms; Malignant neoplasm of gastrointestinal tract; Mediating; Mesenchymal; Molecular; Morphogenesis; Mus; Neoplasm Metastasis; Nuclear; Nuclear Import; Organ; Outcome; Pancreas; Pathology; Pathway interactions; Patients; Pharmaceutical Preparations; Phase; Phosphorylation; Physiological; Physiological Processes; Play; Process; Property; Proteins; Receptor Protein-Tyrosine Kinases; Recurrence; Regulation; Reporting; Research; Research Design; Resources; Respiratory System; Respiratory tract structure; Risk; Role; SRC gene; Severe Combined Immunodeficiency; Signal Pathway; Signal Transduction; Solid Neoplasm; Specimen; Stem cells; Stomach; Testing; Therapeutic; Therapeutic Agents; Time; Tissue Microarray; Tissues; Transcription Coactivator; Translating; Tumor Cell Invasion; Wound Healing; brush border membrane; cancer therapy; cell motility; cell type; clinically significant; cohort; design; effective therapy; epithelial to mesenchymal transition; fibrogenesis; gastrointestinal; gene therapy; improved; in vivo; injured; intestinal homeostasis; meetings; mortality; new therapeutic target; novel; novel therapeutics; outcome forecast; prevent; prognostic; programs; protein-tyrosine kinase c-src; repaired; research study; senescence; slug; therapeutic DNA; tissue regeneration; tissue repair; trafficking; tumor progression; tumorigenesis; villin

DESCRIPTION (provided by applicant): Epithelial-mesenchymal transition (EMT) is a highly conserved cellular program that allows polarized, immotile epithelial cells to convert to motile mesenchymal cells. EMT is fundamental for tissue remodeling events during development, but this process is re-engaged in adults during wound healing, tissue regeneration, organ fibrosis, tumor invasion and metastasis. While the physiological and clinical significance of EMT is overwhelming, the precise molecular and functional features of EMT remain poorly characterized. Villin is an epithelial cell specific actin-binding protein that is expressed in mos significant amounts in the gastrointestinal, urogenital and respiratory tracts. Villin is a multifunctional protein that regulates epithelial cell plasticity and EMT amongst other functions. Studies done with the villin knockout mice have clearly demonstrated that the absence of villin impairs the ability of epithelial cells to respond to signals that regulate EMT, resulting in a deficiency in wound repair and cell migration. Despite these findings, how villin actuates changes in EMT remains to be determined. In our preliminary studies, we demonstrate for the first time that villin localizes to the nucleus and interacts directly with a transcriptional co-regulator, ZBRK1. Furthermore, we report that nuclear villin activates the expression of the transcriptional factor Slug to modulate epithelial plasticity and EMT. Most importantly, our studies suggest that mislocalization of villin away from the brush border membrane is prognostic of increased mortality in patients with colorectal cancer. Studies designed in this application wil test our novel hypothesis that cytoplasmic-nuclear trafficking of villin regulates the stability and/or turnover of the transcriptional co-regulator ZBRK1, thereby modulating the expression of the key transcriptional factor Slug to induce EMT. Additional studies are designed to link the abnormal nuclear localization of villin with metastasis in patients with colorectal cancer. Specifically, the goal of the proposed studies are: (i) to validate the molecular mechanism(s) that regulates the cytoplasmic-nuclear trafficking and nuclear retention of villin; (ii) to characterize the villin-ZBRK1 complex and its role in the expression of Slug, a key transcriptional activator of EMT and; (iii) to elucidate the function of nuclear villin in the regulation of EMT and metastasis. The experimental approach we have proposed combines mechanistic and functional biochemical, cell and molecular biological studies together with in vivo studies in the villin-/-, villin+/+, ApcMin/villin-/-; ApcMin/villin+/+, and severe combined immunodeficiency mice (SCID) mice to allow us to unravel the complex question of how EMT is regulated. Additional studies are proposed using two unique human colon cancer tissue microarray resources namely, a cohort of 334 clinical trial specimens from patients enrolled in phase III MAX trial and a tissue microarray (TMA) of 29 matched primary and metastatic colon tumor specimens. The long-term goal of our studies is to translate our findings into clinical outcomes to diagnose, prevent and/or treat fibrosis and metastasis.

描述（由申请人提供）：上皮间质转化（EMT）是一种高度保守的细胞程序，允许极化的、不活动的上皮细胞转化为活动的间充质细胞。 EMT 对于发育过程中的组织重塑事件至关重要，但这一过程在成人的伤口愈合、组织再生、器官纤维化、肿瘤侵袭和转移过程中会重新参与。虽然 EMT 的生理和临床意义是压倒性的，但 EMT 的精确分子和功能特征仍然知之甚少。绒毛蛋白是一种上皮细胞特异性肌动蛋白结合蛋白，在胃肠道、泌尿生殖道和呼吸道中表达量最大。 Villin 是一种多功能蛋白，可调节上皮细胞可塑性和 EMT 等功能。对绒毛蛋白基因敲除小鼠进行的研究清楚地表明，绒毛蛋白的缺失会损害上皮细胞对调节 EMT 信号的反应能力，导致伤口修复和细胞迁移的缺陷。尽管有这些发现，villin 如何引起 EMT 变化仍有待确定。在我们的初步研究中，我们首次证明了 villin 定位于细胞核并直接与转录辅助调节因子 ZBRK1 相互作用。此外，我们报告核绒毛激活转录因子 Slug 的表达来调节上皮可塑性和 EMT。最重要的是，我们的研究表明绒毛错位远离刷状缘膜预示着结直肠癌患者死亡率增加。本申请设计的研究将检验我们的新假设，即绒毛蛋白的细胞质-核运输调节转录辅助调节因子 ZBRK1 的稳定性和/或周转，从而调节关键转录因子 Slug 的表达以诱导 EMT。其他研究旨在将绒毛蛋白的异常核定位与结直肠癌患者的转移联系起来。具体来说，拟议研究的目标是：（i）验证调节绒毛细胞质-核运输和核保留的分子机制； (ii) 表征villin-ZBRK1复合物及其在Slug表达中的作用，Slug是EMT的关键转录激活因子； (iii) 阐明核绒毛蛋白在 EMT 和转移调节中的功能。我们提出的实验方法将机械和功能生化、细胞和分子生物学研究与villin-/-、villin+/+、ApcMin/villin-/-的体内研究结合起来； ApcMin/villin+/+ 和严重联合免疫缺陷小鼠 (SCID) 小鼠使我们能够解开 EMT 如何调节的复杂问题。提议使用两种独特的人类结肠癌组织微阵列资源进行其他研究，即来自参加 III 期 MAX 试验的患者的 334 份临床试验样本的队列和由 29 份匹配的原发性和转移性结肠肿瘤样本组成的组织微阵列 (TMA)。我们研究的长期目标是将我们的发现转化为临床结果，以诊断、预防和/或治疗纤维化和转移。