Control of Glioma Cell Invasion By Immunotherapy

通过免疫疗法控制胶质瘤细胞侵袭

• 批准号: 7141596
• 负责人: ELIZABETH W. NEWCOMB
• 金额: $ 22.82万
• 依托单位: NEW YORK UNIVERSITY SCHOOL OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-15 至 2008-05-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7141596
• 关键词: active immunization; glioma; immunotherapy; neoplasm /cancer

DESCRIPTION (provided by applicant): Presently, there is no known therapy that can target invading glioma tumor cells. In order to study the biological properties of invading glioma cells at the molecular level, we have developed an in vivo animal model using green fluorescent protein (GFP)-tagged murine GL261 glioma cells. This allows us to identify invading glioma cells into the brain adjacent to the main tumor mass using GFP immunohistochemistry. Microarray gene technology high-lighted differences in gene expression profiles between invading and non-invading human glioma cells identifying MHC class I molecules as a potential target for novel immunotherapeutic approaches. The GL261 glioma cell line is poorly immunogenic due to its low expression of MHC molecules. However, we have shown that low dose whole brain radiation therapy (WBRT) of an established GL261 tumor up-regulates MHC expression on invading GL261 glioma cells in vivo. In the present application we will continue to test the hypothesis that low dose WBRT to the GL261 intracranial tumor will up-regulate MHC expression providing a target(s) for a T-cell mediated antitumor immune response directed towards the invading cells and improve the efficacy of immunotherapy. In Aim 1 we will determine the optimal dose and time course to up-regulate MHC expression on invading glioma cells and optimal number of vaccinations to increase long-term survivals, respectively (1a); and to determine host's immune response elicited by the combination of WBRT and vaccination (V). The WBRT schedule of 4 Gy alone induces an inflammatory response associated with an influx of TILs at the tumor site. Brains will be characterized for TILs by FACS analysis and immunohistochemistry of frozen section at 1 week and 2 weeks following treatments. (1b). In Aim 2, we will determine the effects of MHC overexpression in GL261 tumor cells on their growth, invasion and immunogenicity in vitro and in vivo. GL261 tumor cells will be engineered to stably express an inducible construct (Tet-On) encoding the murine CIITA cDNA, a gene that regulates expression of the MHC complex. In Aim 3, we will determine whether up-regulation of MHC expression on invading GL261 tumor cells in vivo is required for the improved therapeutic effect of vaccination following WBRT. MHC expression will be inhibited using siRNA technology. The growing awareness that low dose irradiation can make tumors more amenable to recognition by the patients' immune system forms the basis of our rationale combining cancer vaccines with local irradiation of the brain tumor.

描述(申请人提供)：目前，还没有已知的治疗方法可以针对侵袭性胶质瘤肿瘤细胞。为了从分子水平研究胶质瘤侵袭性细胞的生物学特性，我们利用绿色荧光蛋白(GFP)标记的小鼠GL261胶质瘤细胞建立了体内动物模型。这使我们能够利用GFP免疫组织化学来识别邻近主要肿瘤肿块的脑内侵袭性胶质瘤细胞。微阵列基因技术突出了侵袭性和非侵袭性人类胶质瘤细胞之间基因表达谱的差异，确定MHC I类分子是新的免疫治疗方法的潜在靶点。GL261胶质瘤细胞系由于其低表达MHC分子而免疫原性差。然而，我们已经证明，对已建立的GL261肿瘤进行低剂量全脑放射治疗(WBRT)可上调体内侵袭性GL261胶质瘤细胞上MHC的表达。在目前的应用中，我们将继续检验这样的假设，即小剂量照射GL261颅内肿瘤将上调MHC的表达，为针对侵袭细胞的T细胞介导的抗肿瘤免疫反应提供靶点(S)，并提高免疫治疗的效果。在目标1中，我们将分别确定上调侵袭性胶质瘤细胞MHC表达的最佳剂量和时间，以及提高长期存活率的最佳疫苗接种次数(1a)；并确定WBRT和疫苗接种(V)组合所引发的宿主免疫反应。仅4GyWBRT方案就会引起与肿瘤部位TIL涌入相关的炎症反应。分别于治疗后1周和2周通过流式细胞仪分析和冰冻切片免疫组织化学方法检测脑组织中的TIL。(1B)。在目的2中，我们将在体内外研究MHC在GL261肿瘤细胞中过表达对其生长、侵袭和免疫原性的影响。GL261肿瘤细胞将被设计成稳定表达编码小鼠CIITA cDNA的可诱导结构(Tet-on)，这是一种调节MHC复合体表达的基因。在目标3中，我们将确定是否需要上调体内侵袭性GL261肿瘤细胞上MHC的表达，以改善WBRT后接种疫苗的治疗效果。利用siRNA技术将抑制MHC的表达。人们越来越意识到，低剂量辐射可以使肿瘤更容易被患者的免疫系统识别，这构成了我们将癌症疫苗与脑瘤局部照射相结合的理论基础。