Small integrin-binding proteins and tumor progression

小整合素结合蛋白与肿瘤进展

• 批准号: 7147389
• 负责人: NEAL S FEDARKO
• 金额: $ 24.5万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-15 至 2009-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7147389
• 关键词: binding proteins; integrins; neoplasm /cancer; protein binding; siblings

DESCRIPTION (provided by applicant): A family of secreted proteins, which we term SIBLINGS (for Small Integrin-Binding LIgand, N-linked Glycoproteins), contain the integrin-binding tripeptide, ROD, are expressed in the skeleton and have genes clustered on human chromosome 4. Our work and that of others has shown that a variety of neoplasms frequently express one or more of the proteins and that expression correlates with disease severity. We have recently found that SIBLINGS can bind to and modulate the activity of matrix metalloproteinases (MMPs). SIBLING binding to latent pro-MMPs leads to catalytic activity, and SIBLING binding to MMPs inhibited by tissue inhibitors of metalloproteinases (TIMPs) or small molecular weight inhibitors leads to a restoration of enzymatic activity. We hypothesize that SIBLING expression by neoplasms promotes tumor progression through MMP modulation. To test this hypothesis, we will (a) characterize SIBLING and MMP interactions using purified components and standard sequence and kinetic analyses to characterize SIBLING effects of MMP and MMP inhibitor kinetics as well as identify SIBLING modifying reagents; (b) test SIBLING- modifying reagents (variants, blocking peptides, antibodies) in in vitro cell systems that yield a functional readout on angiogenesis (endothelial cells and tubule formation) and invasiveness (human cancer cells and modified Boyden chamber assays); and (c) employ SIBLINGS, SIBLING-modifying reagents to demonstrate the physiological relevance of SIBLING - MMP interactions in tumor progression (using two quantitative chick embryo chorioallantoic membrane (CAM) systems to study angiogenesis and metastasis). The CAM angiogenesis assay employs the implantation of SIBLING reagents in a collagen gel within a nylon mesh and quantifying vessel formation. The CAM metastasis assay uses a highly sensitive assay based on PCR amplification of human alu sequences for monitoring the metastatic dissemination of human tumor cells in the chick embryo. The molecular action of SIBLINGS in modulating MMPs may contribute to tumor progression. The alteration of MMP activity by SIBLINGS and their expression in human cancer may be a contributory factor to the failure of MMP inhibitors in clinical trials. It is the long term goal of this work to exploit knowledge of the basic biochemical and biological details involved in SIBLING binding to MMP to develop anti-tumor growth and progression therapy based on disrupting or altering SIBLING - MMP interactions.

描述（由申请人提供）：分泌蛋白家族，我们称之为 SIBLINGS（小整合素结合配体，N 连接糖蛋白），包含整合素结合三肽 ROD，在骨架中表达，并具有聚集在人类 4 号染色体上的基因。我们和其他人的工作表明，多种肿瘤经常表达一种或多种蛋白质，并且表达与 疾病的严重程度。我们最近发现 SIBLINGS 可以结合并调节基质金属蛋白酶 (MMP) 的活性。 SIBLING 与潜在的 MMP 前体结合会产生催化活性，而 SIBLING 与被金属蛋白酶组织抑制剂 (TIMP) 或小分子量抑制剂抑制的 MMP 结合会导致酶活性恢复。我们假设肿瘤表达的 SIBLING 通过 MMP 调节促进肿瘤进展。为了检验这一假设，我们将 (a) 使用纯化组分和标准序列和动力学分析来表征 SIBLING 和 MMP 相互作用，以表征 MMP 和 MMP 抑制剂动力学的 SIBLING 效应，并鉴定 SIBLING 修饰试剂； (b) 在体外细胞系统中测试 SIBLING 修饰试剂（变体、封闭肽、抗体），产生血管生成（内皮细胞和肾小管形成）和侵袭性（人类癌细胞和改良的博伊登室测定）的功能读数； (c) 使用 SIBLINGS、SIBLING 修饰试剂来证明 SIBLING - MMP 相互作用在肿瘤进展中的生理相关性（使用两个定量鸡胚绒毛尿囊膜 (CAM) 系统来研究血管生成和转移）。 CAM 血管生成测定采用将 SIBLING 试剂植入尼龙网内的胶原凝胶中并量化血管形成。 CAM 转移检测采用基于人 alu 序列 PCR 扩增的高灵敏度检测，用于监测鸡胚中人肿瘤细胞的转移扩散。 SIBLINGS 调节 MMP 的分子作用可能有助于肿瘤进展。 SIBLINGS对MMP活性的改变及其在人类癌症中的表达可能是MMP抑制剂在临床试验中失败的一个促成因素。这项工作的长期目标是利用 SIBLING 与 MMP 结合所涉及的基本生化和生物学细节的知识，开发基于破坏或改变 SIBLING - MMP 相互作用的抗肿瘤生长和进展疗法。