Therapeutic Evaluation of Magnetic Nanoprobes Specific for Malignant Tumor Marker

描述（由申请人提供）：本项目的范围是确定对肿瘤标志物（如c-Met（肝细胞生长/分散因子酪氨酸激酶受体）或VEGF-R2（血管内皮生长因子受体））具有特异性的磁铁矿或氧化铁（IO）纳米探针是否可用于治疗，以抑制或减少实验啮齿动物模型中的神经胶质瘤肿瘤生长。我们计划开发和合成IO纳米探针，或特征性肿瘤抗原特异性抗体标记的基于IO的MRI造影剂，用于在大鼠胶质瘤模型中体内检测与肿瘤恶性或血管生成相关的分子事件。我们将评估这些IO纳米探针检测恶性肿瘤标志物的能力，例如在实验性C6大鼠胶质瘤模型中，在侵袭性肿瘤中过度表达的c-MET和与恶性肿瘤血管生成相关的VEGF-R2。最近还确定IO纳米颗粒可以通过经受交变磁场（AMF）来诱导高热，并且这可以用作针对肿瘤的可能的治疗方式。在一种新的方法中，我们希望将IO纳米颗粒的治疗性质和肿瘤标志物特异性纳米探针的特异性结合联合收割机，以将热疗疗法导向由抗c-Met或抗VEGF-R2纳米探针靶向的恶性肿瘤。将使用分子磁共振成像（mMRI）评估纳米探针对c-Met或VEGF-R2的特异性，并将使用形态学MRI评估纳米探针对大鼠胶质瘤模型中胶质瘤生长的疗效。重要的是，在开发临床诊断和/或治疗方法之前，首先在实验动物模型中研究验证步骤。MRI作为一种分子成像方式的优点是具有更高的空间分辨率（5 m），并且能够在单次成像中获得形态学、生理学和代谢信息。我们将用于评估肿瘤标志物特异性纳米探针作为潜在诊断和治疗剂的具体目标如下：（1）评估肿瘤标志物特异性磁铁矿纳米探针检测与肿瘤恶性和血管生成相关的标志物的能力，以及（2）评估纳米探针在与交变磁场一起使用时的抗肿瘤治疗效果。对于具体目标1，我们计划将IO纳米颗粒与抗VEGF-R2 Ab或抗c-Met Ab结合共价结合到交联IO（克利奥）上，使得它们可以用作血管纳米探针。基于葡聚糖的克利奥造影剂先前已被用作“血池”剂。IO纳米探针将在我们实验室广泛使用的C6大鼠胶质瘤模型中进行测试。对于非特异性对照，将正常非免疫大鼠IgG偶联至克利奥部分。对于具体目标2，重点将是将纳米探针的肿瘤标志物特异性联合收割机组合以靶向恶性肿瘤，并利用这些化合物上的IO组分作为经由交变磁场（100 kHz至500 kHz频率范围）产生高热的手段，作为可能的抗肿瘤治疗性治疗。我们计划在给予靶向c-Met或VEGF-R2的IO纳米探针后，将携带C6胶质瘤的大鼠置于交变磁场（AMF）中，并通过MRI监测肿瘤生长。对照组将用非特异性IO纳米颗粒（含有正常非免疫大鼠IgG）处理，并进行AMF。拟议的研究具有高度创新性，涉及分子靶向剂，磁性纳米探针以及与这些纳米探针相关的治疗选择的研究和开发，可用于抑制生长并可能根除恶性胶质瘤。我们的计划是将纳米颗粒的潜在热疗治疗效果与针对恶性肿瘤的肿瘤标记物的特异性结合起来。以前从未尝试过通过在神经胶质瘤模型内靶向c-MET或VEGF-R2来实现概念的这种组合。体内生物医学研究工具的发展，以评估潜在的肿瘤生物标志物的检测可能有显着的影响，未来的诊断方法，用于早期检测人类胶质瘤。此外，该项目还将评估潜在药物预防恶性胶质瘤形成的化学预防能力。为了实现该项目的目标，我们组建了一个来自俄克拉荷马州医学研究基金会（OMRF）、俄克拉荷马州州立大学（OSU）和中央俄克拉荷马州大学（UCO）的多机构团队，他们在mMRI、纳米颗粒、射频生物工程和癌症治疗方面具有专业知识。公共卫生相关性：该项目的重点是开发和评估肿瘤标志物特异性磁铁矿或氧化铁（IO）纳米探针在体内检测肿瘤标志物的能力，并将其用作抗癌治疗剂。IO纳米探针，如超小超顺磁性氧化铁（USPIO）最近已成为流行的分子报告探针与分子磁共振成像（mMRI）的使用。我们建议在啮齿动物胶质瘤模型中使用分子磁共振成像（mMRI）开发和评估IO纳米探针，以跟踪与肿瘤恶性程度和血管生成相关的分子标志物，并利用纳米探针本身作为潜在的治疗剂。研究一种潜在有效的抗肿瘤治疗剂，以及开发新的体内诊断和预测程序可能会显着影响患者的预后和生存能力在未来。

DESCRIPTION (provided by applicant): The scope of this project is to establish whether magnetite or iron oxide (IO) nanoprobes, specific for tumor markers such as c-Met (tyrosine kinase receptor for the hepatocyte growth/scatter factor) or VEGF-R2 (vascular endothelial growth factor receptor), can be used therapeutically to inhibit or diminish glioma tumor growth in experimental rodent models. We plan to develop and synthesize IO nanoprobes, or characteristic tumor antigen-specific antibody tagged IO-based MRI contrast agents, for the in vivo detection of molecular events associated with tumor malignancy or angiogenesis in rat glioma models. We will assess the ability of these IO nanoprobes to detect malignant tumor markers such as c-MET, over-expressed in tumors that are invasive in nature, and VEGF-R2, which is associated with angiogenesis in malignant tumors, in an experimental C6 rat glioma model. It has also been recently established that IO nanoparticles can induce hyperthermia by being subjected to an alternating magnetic field (AMF), and that this may be used as a possible therapeutic modality against tumors. In a novel approach, we wanted to combine the therapeutic nature of the IO nanoparticles, and the specificity of tumor marker specific nanoprobes to direct hyperthermia therapy to malignant tumors targeted by anti-c-Met or anti-VEGF-R2 nanoprobes. Molecular magnetic resonance imaging (mMRI) will be used to assess the nanoprobe specificity for either c-Met or VEGF-R2, and morphological MRI will be used to assess the therapeutic efficacy of the nanoprobes on glioma growth in a rat glioma model. It is important that validation steps are initially studied in experimental animal models prior to the development of methods for clinical diagnosis and/or treatment. The advantages of MRI as a molecular imaging modality are a higher spatial resolution (5m) and the ability to obtain morphological, physiological and metabolic information in a single imaging session. The specific aims that we will use to assess tumor marker specific nanoprobes as potential diagnostic and therapeutic agents are as follows: (1) Assess tumor marker specific magnetite nanoprobes in their ability to detect markers associated with tumor malignancy and angiogenesis, and (2) assess anti-tumor therapeutic effect of nanoprobes when used with an alternating magnetic field. For specific aim 1, we plan to covalently bind the IO nanoparticles to cross-linked IO (CLIO) in conjunction with anti-VEGF-R2 Ab or anti-c-Met Ab, so that they can be used as vascular nanoprobes. Dextran-based CLIO contrast agents have been previously used as 'blood pool' agents. The IO nanoprobes will be tested in a C6 rat glioma model extensively used in our laboratory. For a non-specific control, a normal non-immune rat IgG will be coupled to the CLIO moiety. For specific aim 2, the focus will be to combine the tumor marker specificity of the nanoprobes to target malignant tumors, and to utilize the IO component on these compounds as a means of generating hyperthermia via an alternating magnetic field (100 kHz to 500 kHz frequency range) as a possible anti-tumor therapeutic treatment. We plan to subject C6 glioma-bearing rats to alternating magnetic fields (AMF), following administration of IO nanoprobes targeting either c-Met or VEGF-R2, and monitor tumor growth via MRI. Controls will be treated with non-specific IO nanoparticles (containing normal non-immune rat IgG) and subjected to an AMF. The proposed research is highly innovative and involves the research and development of molecular targeting agents, magnetic nanoprobes, and therapeutic options associated with these nanoprobes, that can be used to inhibit the growth and possibly eradicate malignant gliomas. Our plan is to incorporate the potential hyperthermia therapeutic effect of the nanoparticles in combination with the specificity of targeting tumor markers on malignant tumors. This combination of concepts has never been attempted before by targeting c- MET or VEGF-R2 within a glioma model. The development of in vivo biomedical research tools to assess the detection of potential tumor biomarkers may have a significant impact on future diagnostic approaches to be used in the early detection of human gliomas. In addition, this project will also assess the chemo-preventative capabilities of potential agents in their ability to prevent malignant glioma formation. To accomplish the goals of the project we have compiled a multi-institutional team from the Oklahoma Medical Research Foundation (OMRF), Oklahoma State University (OSU), and the University of Central Oklahoma (UCO), with expertise in mMRI, nanoparticles, radiofrequency bio-engineering, and cancer therapeutics. PUBLIC HEALTH RELEVANCE: This project is focused on developing and assessing tumor marker specific magnetite or iron oxide (IO) nanoprobes in their ability to detect tumor markers in vivo, and in addition be used as anti-cancer therapeutic agents. IO nanoprobes, such as ultrasmall superparamagnetic iron oxides (USPIOs) have recently become popular as molecular reporting probes with the use of molecular magnetic resonance imaging (mMRI). We propose to develop and assess IO nanoprobes with the use of molecular magnetic resonance imaging (mMRI) in a rodent glioma model to follow molecular markers associated with tumor malignancy and angiogenesis, and to utilize the nanoprobes themselves as potential therapeutic agents. Studying a potentially effective anti- tumor therapeutic agent, as well as developing novel in vivo diagnostic and predictive procedures may significantly impact patient prognosis and survivability in the future.