Expressing New Tumor Antigens by Inhibition of Nonsense Mediated mRNA Decay

通过抑制无义介导的 mRNA 衰变表达新的肿瘤抗原

基本信息

批准号：
8610902
负责人：
Eli Gilboa
金额：
$ 30.8万
依托单位：
UNIVERSITY OF MIAMI SCHOOL OF MEDICINE
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-03-01 至 2016-02-29
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8610902
关键词：
Address Adjuvant Antibodies Antigens Binding Biological Availability Breast Cancer Model Breast Carcinoma Cancer Patient Cancer Vaccines Cells Chemicals Clinical Colon Carcinoma Development Dose Drug Kinetics Epitopes Frequencies Glutamate Carboxypeptidase II Goals Gold Granulocyte-Macrophage Colony-Stimulating Factor Guidelines Human IL2RA gene Immune Immune response Immune system Immunity In Situ In Vitro Injection of therapeutic agent Lesion Ligands Mediating Messenger RNA Modality Modeling Mus Nature Neoplasm Metastasis Nonsense Codon Normal tissue morphology Oligonucleotides Peptides Physiological Process Protocols documentation Rattus Reagent Regulatory T-Lymphocyte Role Site Small Interfering RNA Technology Testing Tumor Antigens Tumor Immunity Vaccination aptamer base cost effective immunogenicity lung melanoma mRNA Decay mRNA Expression mRNA Surveillance neoplastic cell novel novel strategies pathogen pre-clinical prevent public health relevance subcutaneous tumor tumor growth tumor progression uptake

项目摘要

DESCRIPTION (provided by applicant): The main reason why tumors are not controlled by the immune system of the cancer patient is that, unlike pathogens, tumors do not express potent tumor antigens that can be recognized by the immune system as "foreign". The current focus in developing immune-based modalities is to potentiate an immune response against the existing, albeit weak, antigens expressed in the tumor. An alternative approach - the focus of this proposal - is to express new, and hence potent, antigens in tumor cells in situ. Two main challenges that have precluded the development of such strategies, how to express new antigens in the disseminated tumor lesions of the cancer patients and how to restrict expression of such antigens to the tumor, precluding their expression in normal tissue, are addressed by the approach described in this proposal. Expression of novel antigens in tumor cells will be achieved using siRNA technology to inhibit nonsense mediated mRNA decay (NMD), a surveillance mechanism which prevents the expression of mRNAs containing a premature termination codon. Targeting siRNA inhibition to tumor cells - an essential requisite because of the constitutive nature and physiological roles of the NMD process - will be achieved using a novel targeting technology comprised of oligonucleotide aptamer ligands. Aptamers or aptamer targeted siRNA conjugates, unlike antibodies, can be synthesized in a chemical process, providing a more straightforward and cost effective manufacturing and regulatory approval process to generate clinical grade reagents. The hypotheses tested in this proposal - supported by extensive preliminary studies - are: (I). NMD inhibition in tumor cells will result in the expression of novel products which will function as tumor rejection antigens eliciting an immune response that will negatively impact on tumor growth, and (II). Aptamer-targeted siRNA inhibition of NMD in tumor-bearing mice is sufficiently robust to inhibit tumor growth. The main objectives of the proposed studies-carried out in preclinical murine models - are to provide proof-of-concept that tumor targeted inhibition of NMD using aptamer-siRNA conjugates will elicit tumor immunity, and to determine how effective is the this novel approach, compared to best-in-class "conventional" tumor vaccination protocols in preventing and reversing tumor progression in mice. The specific aims of this proposal are: (1). To develop and characterize in vitro best-in-class PSMA aptamer targeted siRNAs corresponding to murine NMD-specific factors. (2). To evaluate the ability of PSMA aptamer-siRNA conjugates to engender antitumor immunity in tumor bearing mice. (3). To develop Her2 aptamer-siRNA conjugates and evaluate their ability to inhibit tumor growth in transplantable and spontaneous murine models for breast cancer. Successful completion of the studies proposed in this application will provide the rationale and guidelines for exploring aptamer targeted NMD inhibition to potentiate tumor immunogenicity in cancer patients.

描述（由申请人提供）：不受癌症患者免疫系统控制的肿瘤的主要原因是，与病原体不同，肿瘤不能表达可被免疫系统识别为“外源”的有效肿瘤抗原。目前开发基于免疫的方式的重点是增强针对肿瘤中表达的现有抗原的免疫反应。另一种方法 - 该提案的重点 - 是在原位表达新的，因此有效的抗原。排除了这种策略的发展的两个主要挑战，即如何在癌症患者的传播肿瘤病变中表达新的抗原以及如何将这种抗原表达在肿瘤中的表达，从而阻止其在正常组织中的表达，这是通过该提案中描述的方法来解决的。使用siRNA技术，将实现肿瘤细胞中新型抗原的表达，以抑制废话介导的mRNA衰变（NMD），这是一种监测机制，可阻止含有过早终止密码子的mRNA表达。靶向siRNA对肿瘤细胞的抑制作用（由于NMD过程的构成性质和生理作用，这是必不可少的必要条件 - 将使用由寡核苷酸适体配体组成的新型靶向技术来实现。与抗体不同，适体或适体的靶向siRNA结合物可以在化学过程中合成，从而提供更直接，更具成本效益的制造和监管批准过程，以生成临床级试剂。在本提案中检验的假设（由广泛的初步研究支持）为：（i）。 NMD抑制在肿瘤细胞中将导致新型产物的表达，这些产品将充当肿瘤排斥反应抗原，引起免疫反应，会对肿瘤生长产生负面影响，并且（ii）。符合肿瘤小鼠中NMD的适体靶向siRNA抑制足以抑制肿瘤生长。 The main objectives of the proposed studies-carried out in preclinical murine models - are to provide proof-of-concept that tumor targeted inhibition of NMD using aptamer-siRNA conjugates will elicit tumor immunity, and to determine how effective is the this novel approach, compared to best-in-class "conventional" tumor vaccination protocols in preventing and reversing tumor progression in mice.该提案的具体目的是：（1）。开发和表征与鼠NMD特异性因素相对应的靶向siRNA的体外最佳PSMA适体。（2）。评估PSMA适体 - 丝娜结合物在轴承小鼠肿瘤中产生抗肿瘤免疫力的能力。（3）。为了开发HER2适体 - siRNA结合物，并评估其抑制乳腺癌的可移植和自发鼠模型中肿瘤生长的能力。成功完成本申请中提出的研究将提供探索适体目标NMD抑制以增强癌症患者肿瘤免疫原性的基本原理和指南。