Myeloma stem cell and cancer testis antigens

骨髓瘤干细胞和癌睾丸抗原

基本信息

批准号：
8050619
负责人：
Barbara Savoldo
金额：
$ 16.23万
依托单位：
METHODIST HOSPITAL RESEARCH INSTITUTE
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-04-01 至 2013-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8050619
关键词：
Age Allogenic Antigen Targeting Bone Marrow CTAG1 gene Carrier Proteins Cell Line Cells Clinical Clinical Data Clinical Trials Cytotoxic T-Lymphocytes Data Disease Dyes Exposure to Fluorescence Future Gametogenesis Genetic Transcription Goals Herpesvirus 1 Human Immunotherapy Knowledge Lead Life Luc Gene MAGED1 gene Malignant Neoplasms Marrow Mesenchymal Stem Cells Methods Methylation Modeling Monitor Morbidity - disease rate Multiple Myeloma Mus Normal tissue morphology Outcome Patients Pharmaceutical Preparations Plasma Cells Play Population Pre-Clinical Model Predisposition Property Proteins Pump Recurrent disease Relapse Reporting Resistance Sampling Side Stem cell transplant Stem cells Stromal Cells System T-Lymphocyte TK Gene Testing Therapeutic Translating Treatment Efficacy Work base cancer stem cell cancer testis antigen cell killing chemotherapy conditioning design experience human stem cells immunogenicity improved in vivo killings mortality neoplastic cell novel pre-clinical public health relevance response standard care stem cell niche tumor tumorigenesis

项目摘要

DESCRIPTION (provided by applicant): Multiple myeloma (MM) is a common hematological cancer that with standard treatment is rarely curable. Although myeloma patients treated with immunomodulatory agents and or chemotherapy may experience a complete clinical response, the majority will eventually relapse. More aggressive treatments including allogeneic stem cell transplantation may be curative, but the high morbidity and mortality of myeloablative conditioning precludes use in many patients. The objective of this project is to develop a preclinical model of targeting myeloma stem cells with immunotherapy that in the long-term can be developed into a novel clinical therapeutic strategy that will improve outcomes for patients with myeloma. We and others have previously described a population of myeloma stem cells that possess clonogenic potential, are highly resistant to chemotheraputics agents, and can initiate tumorigenesis. One of the mechanisms that stem cells use to limit their exposure to chemotherapy is to express transport proteins that can pump out drug. This property of stem cells can be exploited for their purification, since the same transporters efflux Hoechst dye forming a distinct side population on flow cytometric analysis. These cells are likely to play a key role in disease relapse. We now propose to target these myeloma stem cells with immunotherapy directed against cancer testis antigens (CTAs). CTAs are expressed aberrantly in multiple myeloma, and by virtue of their immunogenecity and restricted expression in normal tissue such that T-cell tolerance does not develop, makes CTAs a promising antigen target in myeloma. Additionally, it was recently reported that some CTAs including NRAGE, NY-ESO, MAGE-1, and SSX are expressed in human mesenchymal stem cells (MSCs). This suggests that CTA expression may not only be a hallmark of gametogenesis but also a stem cell marker. Based on these observations, we hypothesize that myeloma stem cells preferentially express CTA and are therefore susceptible to killing by CTA specific T-cells. In addition, CTA transcription is partially regulated by methylation, and therefore demethylating agents maybe used to enhance CTA expression in low expressing tumors and increase susceptibility of these tumor cells to CTA-specific T-cell killings. Our hypothesis is supported by our preliminary data that myeloma stem cells from human myeloma cell line, RPMI 8226, have higher expression of several CTAs, including PRAME, CT7 and NY-ESO1, than the mature myeloma cells (Section C.1). Furthermore, we have already generated PRAME specific cytotoxic T- cells (CTLs) that can kill PRAME positive myeloma cells. In aim 1 we will analyze a large panel of myeloma tumor samples to determine if CTA expression is preserved and/or enriched in primary myeloma stem cells. In aim 2 we will determine if CTLs directed to CTA can directly kill myeloma stem cells using a murine myeloma model. PUBLIC HEALTH RELEVANCE: The long-term objective of this project is to improve the outcome of multiple myeloma (MM), a currently incurable common hematological cancer of plasma cell origin, by targeting the cancer stem cell which play a key role in tumorigenesis and disease relapse using cytotoxic T-cells. The primary goal of this proposal is to generate pre- clinical data for using cytotoxic T-cells to target myeloma stem cells. The fundamental models established and knowledge obtained from this proposal will represent the key for the future design of novel methods toward the long-term cure of myeloma.

描述（由申请人提供）：多发性骨髓瘤（MM）是一种常见的血液癌症，采用标准治疗很少能治愈。尽管接受免疫调节剂和/或化疗治疗的骨髓瘤患者可能会出现完全的临床反应，但大多数患者最终会复发。包括同种异体干细胞移植在内的更积极的治疗可能有疗效，但清髓性调理的高发病率和死亡率阻碍了许多患者的使用。该项目的目标是开发一种利用免疫疗法靶向骨髓瘤干细胞的临床前模型，从长远来看，该模型可以发展成为一种新的临床治疗策略，从而改善骨髓瘤患者的预后。我们和其他人之前已经描述了具有克隆形成潜力、对化疗药物高度耐药并且可以启动肿瘤发生的骨髓瘤干细胞群。干细胞用来限制化疗暴露的机制之一是表达可以泵出药物的转运蛋白。干细胞的这一特性可用于纯化，因为相同的转运蛋白流出 Hoechst 染料，在流式细胞术分析中形成独特的侧群。这些细胞可能在疾病复发中发挥关键作用。我们现在建议通过针对癌睾丸抗原（CTA）的免疫疗法来靶向这些骨髓瘤干细胞。 CTA 在多发性骨髓瘤中异常表达，并且由于其免疫原性和在正常组织中的有限表达，使得 T 细胞耐受性不会发展，使得 CTA 成为骨髓瘤中有希望的抗原靶点。此外，最近有报道称，一些 CTA 包括 NRAGE、NY-ESO、MAGE-1 和 SSX 在人间充质干细胞 (MSC) 中表达。这表明 CTA 表达可能不仅是配子发生的标志，而且也是干细胞标记。基于这些观察，我们假设骨髓瘤干细胞优先表达 CTA，因此容易被 CTA 特异性 T 细胞杀死。此外，CTA转录部分受甲基化调节，因此去甲基化剂可用于增强低表达肿瘤中的CTA表达，并增加这些肿瘤细胞对CTA特异性T细胞杀伤的敏感性。我们的假设得到了初步数据的支持，即来自人骨髓瘤细胞系 RPMI 8226 的骨髓瘤干细胞比成熟骨髓瘤细胞具有更高的几种 CTA 表达，包括 PRAME、CT7 和 NY-ESO1（C.1 节）。此外，我们已经生成了可以杀死 PRAME 阳性骨髓瘤细胞的 PRAME 特异性细胞毒性 T 细胞 (CTL)。在目标 1 中，我们将分析大量骨髓瘤肿瘤样本，以确定 CTA 表达是否在原发性骨髓瘤干细胞中保留和/或富集。在目标 2 中，我们将使用小鼠骨髓瘤模型确定针对 CTA 的 CTL 是否可以直接杀死骨髓瘤干细胞。公共健康相关性：该项目的长期目标是通过针对在肿瘤发生和疾病中发挥关键作用的癌症干细胞来改善多发性骨髓瘤（MM）的结果，多发性骨髓瘤是一种目前无法治愈的浆细胞来源的常见血液癌症使用细胞毒性 T 细胞复发。该提案的主要目标是生成使用细胞毒性 T 细胞靶向骨髓瘤干细胞的临床前数据。从该提案中建立的基本模型和获得的知识将成为未来设计长期治愈骨髓瘤的新方法的关键。