Glycan control of stem cell-associated pathways in pancreatic cancer

胰腺癌中干细胞相关通路的聚糖控制

基本信息

批准号：
8986782
负责人：
Susan L Bellis
金额：
$ 15.99万
依托单位：
UNIVERSITY OF ALABAMA AT BIRMINGHAM
依托单位国家：
美国
项目类别：
财政年份：
2015
资助国家：
美国
起止时间：
2015-01-01 至 2017-12-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8986782
关键词：
Adopted Apoptosis Basic Science Behavior Biological Models Cancer Patient Cancer cell line Cell Death Cell Line Cell Separation Cell model Cells Cessation of life Characteristics Charge Clinical Clinical Treatment Coupled Data Development Diagnosis Disease Ductal Ductal Epithelial Cell Employee Strikes Etiology Event Genetically Engineered Mouse Goals Growth Harvest Health Human Integrins K-ras Oncogene Knock-in Knock-out Knowledge Link Malignant - descriptor Malignant Neoplasms Malignant neoplasm of pancreas Modification Molecular Molecular Biology Monitor Mus Neoplasm Metastasis Neoplastic Cell Transformation Oligosaccharides Pancreas Pancreatic Adenocarcinoma Pancreatic Ductal Adenocarcinoma Pathogenesis Pathway interactions Patient Care Patients Pharmaceutical Preparations Phenotype Physiological Polysaccharides Population Primary Neoplasm Property Research Resistance Role ST6Gal I Sialic Acids Signal Transduction Sorting - Cell Movement Staging Stem cells Surface Testing Therapeutic Intervention Time Tissues Translating Up-Regulation Work cancer cell cancer initiation cancer stem cell cancer therapy carcinogenesis cell behavior driving behavior expectation gemcitabine glycosylation glycosyltransferase in vivo innovation knock-down mouse model neoplastic cell novel overexpression pancreatic cancer cells pancreatic neoplasm receptor response self-renewal stem stemness sugar targeted treatment therapeutic target transcription factor translational medicine treatment response tumor tumor growth tumor initiation tumor progression tumor xenograft tumorigenesis

项目摘要

DESCRIPTION (provided by applicant): Abnormal surface glycosylation is a defining feature of a tumor cell, however the functional contribution of glycans to carcinogenesis has been largely ignored. One of the predominant tumor-associated changes is an increase in �6 sialic acid, a negatively-charged sugar added to selected receptors by the ST6Gal-I glycosyltransferase. In preliminary studies we find for the first time that ST6Gal-I is elevated in pancreatic cancer (PC), and that ST6Gal-I upregulation causes PC cells to acquire behaviors characteristic of "cancer stem cells" (CSCs), a stem-like cell population inherently metastatic, resistant to cell death, and insensitive to chemotherapeutic drugs. We have also made the landmark discovery that ST6Gal-I upregulation in PC cells induces expression of the CSC-associated transcription factor, Sox9. Sox9 induction is a pivotal initiating event in pancreatic ductal adenocarcinoma. The goals of this application are to establish a role for ST6Gal-I in: (i) CSC-like behaviors directed by a novel ST6Gal-I-NFkB-Sox9 signaling axis; (ii) PC pathogenesis in genetically engineered mice; and (iii) PC cell resistance to gemcitabine, a first-line PC treatment. To achieve these objectives we will employ unique cell model systems, spontaneous PC murine models with forced ST6Gal-I overexpression or deletion, and patient-derived primary tumor and tumor xenograft tissues. This research will extend fundamental knowledge of how sugars regulate tumor cell behavior, and also impact patient care by identifying ST6Gal-I as a marker for resistant cells and potential clinical target for restoring treatment response. AIM 1: ST6Gal-I signaling through Sox9 promotes stem-like PC behaviors that drive pathogenesis. Patient-derived primary PC cells, or PC cell lines with forced ST6Gal-I expression or knockdown, will be used to test the hypothesis that ST6Gal-I activity stimulates signaling through NFkB-Sox9 to promote CSC behaviors including self-renewal; tumor spheroid growth; and tumor-initiating potential. Co-expression of ST6Gal-I, activated NFkB and Sox9 will be examined in patient pancreatic adenocarcinoma tissues, and spontaneous PC murine models with pancreas-specific ST6Gal-I knockin or knockout will be utilized to establish a role for ST6Gal-I in PC development and progression. AIM 2: ST6Gal-I's contribution to chemoresistance and potential as a therapeutic target. Patient-derived PC cells or cell lines with forced ST6Gal-I expression or knockdown will be treated with gemcitabine to test the hypothesis that ST6Gal-I activity promotes chemoresistance. To show that ST6Gal-Iexpressing cells selectively survive gemcitabine treatment in vivo, ST6Gal-I expression will be quantified in patient-derived tumor xenografts harvested from mice treated with or without gemcitabine. Viable cells will be harvested from the gemcitabine-treated tumor xenografts to obtain an in vivo-selected chemoresistant population. These cells will then be subjected to ST6Gal-I knockdown, followed by gemcitabine treatment, to determine whether gemcitabine sensitivity can be restored in a cell population with known stable resistance.

描述（由申请人提供）：异常的表面糖基化是肿瘤细胞的一个决定性特征，然而聚糖对致癌作用的功能贡献在很大程度上被忽视了，与肿瘤相关的主要变化之一是 6 唾液酸的增加。通过 ST6Gal-I 糖基转移酶将带负电荷的糖添加到选定的受体上。在初步研究中，我们首次发现 ST6Gal-I 在体内升高。 ST6Gal-I 上调导致 PC 细胞获得“癌症干细胞”(CSC) 的行为特征，这是一种本质上具有转移性、对细胞死亡具有抵抗力且对化疗药物不敏感的干细胞样细胞群。还做出了具有里程碑意义的发现，即 PC 细胞中 ST6Gal-I 的上调可诱导 CSC 相关转录因子 Sox9 的表达，这是胰腺中的关键起始事件。该应用的目标是确定 ST6Gal-I 在以下方面的作用：(i) 由新型 ST6Gal-I-NFkB-Sox9 信号轴指导的 CSC 样行为；(ii) 基因工程中的 PC 发病机制。小鼠；和 (iii) PC 细胞对一线 PC 治疗药物吉西他滨的耐药性为了实现这些目标，我们将采用独特的细胞模型系统、强制 ST6Gal-I 过度表达或的自发 PC 小鼠模型。这项研究将扩展糖如何调节肿瘤细胞行为的基础知识，并通过将 ST6Gal-I 确定为耐药细胞的标记物和恢复治疗的潜在临床靶点来影响患者护理。目的 1：通过 Sox9 的 ST6Gal-I 信号传导促进驱动发病机制的干细胞样 PC 行为，或具有强制 ST6Gal-I 表达或敲低的 PC 细胞系。测试 ST6Gal-I 活性通过 NFkB-Sox9 刺激信号传导以促进 CSC 行为（包括自我更新）的假设；并检查患者中 ST6Gal-I、激活的 NFkB 和 Sox9 的共表达潜力。胰腺癌组织和具有胰腺特异性 ST6Gal-I 敲入或敲除的自发性 PC 小鼠模型将用于建立ST6Gal-I 在 PC 发育和进展中的作用。目标 2：ST6Gal-I 对化疗耐药性的贡献以及作为治疗靶点的潜力，将用吉西他滨治疗来测试这一假设。 ST6Gal-I 活性促进化疗耐药性为了表明 ST6Gal-I 表达细胞在体内选择性地存活于吉西他滨治疗，ST6Gal-I 表达将会升高。从用或不用吉西他滨治疗的小鼠收获的患者来源的肿瘤异种移植物中进行定量将从经吉西他滨治疗的肿瘤异种移植物中收获活细胞以获得体内选择的化学抗性群体，然后将这些细胞进行ST6Gal-I敲低。，然后进行吉西他滨治疗，以确定是否可以在具有已知稳定耐药性的细胞群中恢复吉西他滨敏感性。