Targeting AVIL in Glioblastoma

摘要多形性胶质母细胞瘤是最常见和最具侵袭性的原发性脑肿瘤。 人类。尽管进行了多模式的积极治疗，但GBM是致命的--存活时间超过3年是可以考虑的 长期的。显然需要更多的治疗目标和治疗选择。在我们的初步研究中，我们 在GBMS中发现了一种新的癌基因avl。AVIL基因在所有胶质母细胞瘤细胞系中都过表达， 包括胶质母细胞瘤干细胞和临床病例，但在非肿瘤星形胶质细胞、神经细胞中几乎检测不到 干细胞和脑组织。沉默AVIL导致在GBM细胞培养中完全根除，但 对星形胶质细胞对照细胞影响不大。在动物模型中，体内沉默Avil显著受到抑制 小鼠的异种移植。相反，在细胞培养系统中过度表达AVIL会促进肿瘤的发生，使 成纤维细胞逃避接触抑制，并转化为永生化的星形胶质细胞。在患者队列中，更高 AvIL在胶质瘤中的表达水平与预后不良相关。最重要的是，基底膜细胞 对抗癌药物的小分子抑制剂敏感。这些证据支持阿维尔是阿喀琉斯的假设 靶向，这可能是治疗GBM的一种有效方法。在此应用程序中，我们建议使用 AVIL作为抗GBM新靶点的系统研究。目标1：确定靶向的效果 检测AvIL在体外的表达情况，并将其作为敏感性的生物标志物。我们已经展示了反病毒的关键作用 部分GBM和GSC细胞株。在这里，我们将研究它在其他胶质母细胞瘤系、GSCs和 GBM患者来源的异种移植培养的短期外植体及其与 CDK4/MDM2。我们将测试tet诱导的shRNA针对av1和小分子化合物的有效性。 我们通过小分子筛选进行了鉴定。此外，我们还将确定Avil表达式是否用作 一种生物标记物，用于检测对Avil抑制的敏感性。目的2：确定靶向AvIL在动物GBM中的作用 模特们。我们将在异种移植模型中使用shRNA和小分子抑制剂来测试其疗效和 体内靶向抗癌药物的安全性。此外，我们将使用Avil基因敲除小鼠模型，通过将它们与 建立小鼠脑胶质瘤模型，以检测AvIL的表达是否对小鼠脑胶质瘤的形成是必需的。目标3： 研究AVIL抑制的下游靶点和机制，确定潜在的药效学 生物标志物。我们有初步数据表明，AVIL调节Lin28b，FOXM1可能介导了这一作用 在U87细胞中。我们将调查Lin28b和FOXM1是否为Avil的功能关键目标，以及 它们是否为评价AVIL靶向治疗效果的潜在药效学生物标志物 心理治疗。目的4：探讨靶向AvIL的潜在耐药机制。我们的目标是预见到 在临床环境中出现之前，基于AVIL的治疗面临挑战。拟议的研究将有一个 对认识和治疗基底膜有重大影响。这些发现将为打击Avil AS铺平道路 一种新的致癌基因，并导致开发出治疗这种致命疾病的新方法。

Glioblastoma multiforme (GBM), is the most common and most aggressive malignant primary brain tumor in humans. Despite multimodal aggressive therapy, GBM is fatal—with survival over 3 years being considered long-term. More therapeutic targets and treatment options are clearly needed. In our preliminary study, we identified a novel oncogene, AVIL in GBMs. AVIL gene is overexpressed in all the glioblastoma cell lines, including glioblastoma stem cells, and clinical cases, but is hardly detectable in non-cancer astrocytes, neural stem cells, and brain tissues. Silencing AVIL resulted in complete eradication in GBM cell cultures, but had little effect on the astrocyte control cells. In animal models, silencing AVIL dramatically inhibited in vivo xenografts in mice. Conversely, overexpressing AVIL in cell culture systems promoted tumorigenesis, enabled fibroblasts to escape contact inhibition, and transformed immortalized astrocytes. In patient cohorts, higher expression levels of AVIL in gliomas correlated with worse prognosis. Most importantly, GBM cells are more susceptible to small molecule inhibitors of AVIL. These evidences support the premise that AVIL is an Achilles heel of GBMs, targeting which may be an effective approach for GBMs. In this application, we propose the systematic investigation of AVIL as a novel target against GBMs. Aim 1: Determine the efficacy of targeting AVIL in vitro and test AVIL expression as a biomarker of sensitivity. We have shown the critical role of AVIL in some GBM and GSC cell lines. Here, we will investigate its role in additional glioblastoma lines, GSCs, and short-term explants of GBM patient derived xenograft cultures and potential synergistic effect with CDK4/MDM2. We will test the efficacy of tet-inducible shRNAs targeting AVIL, and small molecule compounds we identified through small molecule screen. In addition, we will determine whether AVIL expression serves as a biomarker for sensitivity to AVIL inhibition. Aim 2: Determine the efficacy of targeting AVIL in animal GBM models. We will use shRNA and small-molecule inhibitors in xenograft models to test both the efficacy and safety of targeting AVIL in vivo. In addition, we will use Avil knockout mouse model by crossing them with glioma mouse models to test whether Avil expression is necessary for glioma tumorigenesis in mouse. Aim 3: Investigate the downstream targets and mechanisms of AVIL inhibition and identify potential pharmacodynamic biomarkers. We have preliminary data suggesting AVIL regulates LIN28B, and FOXM1 may mediate the effect in U87 cells. We will investigate whether LIN28B and FOXM1 are functionally critical targets of AVIL, and whether they are potential pharmacodynamic biomarkers to evaluate treatment efficacy of AVIL-targeting therapy. Aim 4: Investigate potential resistance mechanisms of targeting AVIL. The goal is to anticipate challenges to AVIL-based treatment before they arise in the clinical setting. The proposed study will have a significant impact on the understanding and treatment of GBMs. The findings will pave ways to target AVIL as a novel oncogene, and lead to the development of novel therapeutic approaches for the deadly disease.