Targeting eIF2alpha siRNA to alpha(v)beta(3) Integrin-bearing Tumor Cells

描述（由申请人提供）：作为细胞死亡的一种模式，细胞凋亡的优点在于它不引起炎症反应，因此降低了与组织炎症相关的有害局部和全身事件的可能性。真核翻译起始因子eIF 2？被选择作为靶标，因为它在蛋白质合成中很重要，并且是涉及因子eIF 2的该蛋白亚基的特异性磷酸化的几种类型的翻译调节的中心靶标。蛋白质合成的抑制有助于细胞凋亡，并且该过程通常被不同的病毒靶向以诱导细胞凋亡。在这个拟议的项目中，有针对性地交付凋亡eIF 2？siRNA是什么？v？以聚阳离子壳聚糖为载体，对3整合素肿瘤细胞进行了研究。根据已发表的报道，血流中寡核苷酸载体的循环半衰期缩短会阻止足够的寡核苷酸到达靶细胞。减轻eIF 2的吞噬作用？siRNA载体，我们提出将“自身标记”整联蛋白相关蛋白（CD 47）缀合至基于壳聚糖的siRNA载体。除了它的抗吞噬功能，CD 47蛋白结合的siRNA纳米载体将作为一个配体靶向肿瘤细胞高度表达？v？3整合素。建议的CD 47-共轭壳聚糖/siRNA纳米载体预计有很长的半衰期在血液循环中，因此允许更有效的网站结合通过？v？3整合素与诱导肿瘤新生血管凋亡的关系。siRNA。关于该项目的教育方面，该项目的多学科性质将培养学生接受生物医学工程，分子生物学，基因/药物输送和纳米医学方面的培训。除了培养研究生外，本项目的教育计划还将招收几名化学工程专业的本科生，重点是生物化学/生物医学，并为他们提供动手研究的机会。本科生研究人员将积极参与新技术的开发，并探索他们在生物医学领域的职业发展道路。 公共卫生相关性：真核翻译起始因子eIF 2？被选为靶点是因为它在蛋白质合成中很重要。由于蛋白质合成的抑制有助于细胞凋亡，整合素相关蛋白（CD 47）共轭eIF 2？小干扰RNA载体被提议靶向高度表达的肿瘤细胞，v？3整合素和交付凋亡eIF 2？siRNA。

DESCRIPTION (provided by applicant): As a mode of cell death, apoptosis has an advantage in that it does not invoke an inflammatory response, thus there is decrease possibility of deleterious local and systemic events associated with tissue inflammation. Eukaryotic translation initiation factor eIF2? is chosen as a target because it is important in protein synthesis and is a central target of several types of translational regulation involving specific phosphorylation of this protein subunit of factor eIF2. Inhibition of protein synthesis contributes to cellular apoptosis and this process is often targeted by different viruses for the induction of apoptosis. In this proposed project, targeted delivery of apoptotic eIF2? siRNA to ?v?3 integrin-bearing tumor cells using polycationic chitosan as the vector will be studied. According to published accounts, shortened circulatory half-lives of oligonucleotide carriers in the bloodstream prevent sufficient oligonucleotides from reaching the target cells. To mitigate phagocytosis of eIF2? siRNA carriers, we propose to conjugate the "marker of self" integrin-associated protein (CD47) to chitosan-based siRNA carriers. In addition to its antiphagocytic feature, CD47 protein conjugated on siRNA nanovectors will act as a ligand targeted for tumor cells highly expressed with ?v?3 integrins. The proposed CD47-conjugated chitosan/siRNA nanovectors are expected to have much extended half-lives in blood circulation, hence allowing for more efficient site binding via ?v?3 integrin and eliciting apoptosis of tumor neovasculature by eIF2? siRNA. With regard to educational aspect of this project, the multidisciplinary nature of this project will produce students with training in biomedical engineering, molecular biology, gene/drug delivery, and nanomedicine. In addition to training graduate students, the educational plan of this project will recruit several undergraduates that are Chemical Engineering major with biochemical/biomedical emphasis and provide them with the opportunity of hands-on meritorious research. The undergraduate student researchers will actively participate in the development of new technology and explore their possible career path in biomedical fields. PUBLIC HEALTH RELEVANCE: Eukaryotic translation initiation factor eIF2? is chosen as a target because it is important in protein synthesis. Since inhibition of protein synthesis contributes to cellular apoptosis, integrin-associated protein (CD47) conjugated eIF2? siRNA vectors are proposed to target tumor cells highly expressed with ?v?3 integrins and deliver apoptotic eIF2? siRNA.