Exploiting cell fate transition to overcome radiation resistance in glioblastoma

项目摘要 胶质母细胞瘤（GBM）是一种毁灭性的脑肿瘤，每年影响约15，000名美国人。尽管 最大限度的手术切除和放化疗，GBM仍然无法治愈。GBM是出了名的辐射 抵抗通过患者肿瘤的基因组分析对GBM进行分子亚型分型，确定了三种主要亚型， 基于基因表达模式，称为原神经（PN）、经典或间充质（MES）。协同 Sulman和Bhat实验室多年来的努力已经发现了神经胶质瘤干细胞样细胞（GSC） 非常类似于GBM的分子亚型。然而，这些状态表现出可塑性，我们开创了 PN到MES转换的概念基于使用患者衍生的GSC将MES特征与无线电连接的研究- 耐药性和鉴定与MES亚型相关的主转录因子。新的令人兴奋 我们实验室的初步数据已经确定了三个独立的分子靶点， 抗辐射性使用全基因组CRISPR筛选来识别与增强的 辐射敏感性以及辐射诱导蛋白质复合物的质谱评估，我们 已经发现了三个参与代谢、表观遗传和DNA修复途径的参与者， 以克服GSC中的辐射抗性。这项提案的总体目标是将这些可药用目标联合收割机 标准使用分次光子放射治疗（RT），并将GSC从放射抗性转化为 对辐射敏感。在目标1中，我们将检查N-酰基神经氨酸-9-磷酸酶（NANP）的抑制是否会导致 GBM通过代谢重编程从MES转变为PN状态的放射增敏。在目标2中，我们 测试以高迁移率族蛋白盒-2（HMGB 2）为目标是否会导致MES转换和改变的阻塞 染色质，如果它是致命的结合辐射。最后，在目标3中，我们将检查放射增敏 TAZ抑制剂和电离辐射联合应用对神经元分化的影响 GBM。我们的建议是重要的，因为这是第一个全面的研究，以检查放射增敏 GBM中细胞状态转换阻断的影响。从这笔赠款产生的数据将包括TCGA数据集， 患者来源的GSC、临床相关的异种移植模型以及在这些模型中用 进入I期临床试验的轨道，以克服GBM患者的放射抗性。

PROJECT SUMMARY Glioblastoma (GBM) is a devastating brain tumor that affects about 15,000 Americans every year. Despite maximal surgical resection and chemoradiation, GBMs remain incurable. GBMs are notoriously radiation resistant. Molecular subtyping of GBMs by genomic analyses of patient tumors identified three major subtypes, termed Proneural (PN), Classical or Mesenchymal (MES), based on gene expression patterns. Collaborative efforts between the Sulman and Bhat laboratories over the years has uncovered glioma stem-like cells (GSCs) closely resembling molecular subtypes of GBM. These states, however, exhibit plasticity and we pioneered the notion of PN to MES transition based on studies using patient derived GSCs linking MES signatures with radio- resistance and identifying master transcription factors associated with the MES subtype. New exciting preliminary data from our laboratories have identified three independent molecular targets associated with radiation resistance. Using whole-genome CRISPR screens to identify gene targets associated with enhanced radiation sensitivity as well as and mass spectrometric evaluation of radiation induced protein complexes, we have uncovered three players involved in metabolic, epigenetic and DNA repair pathways that can be targeted to overcome radiation resistance in GSCs. The overall goal of this proposal is to combine these druggable targets with the standard use of fractionated photon radiation therapy (RT) and convert GSCs from radioresistant to radiosensitive. In Aim 1, we will examine if inhibition of N-acylneuraminate-9-phosphatase (NANP) will lead to radiosensitization of GBM transitioning from MES to PN states via metabolic reprogramming. In Aim 2, we will test if targeting High Mobility Group Box-2 (HMGB2) leads to a block of MES transitioning and alterations of chromatin and if it is lethal in combination with radiation. Finally, in Aim 3, we will examine the radiosensitizing effects of neuronal differentiation with combined TAZ inhibitors and ionizing radiation in pre-clinical models of GBM. Our proposal is significant because this is the first comprehensive study to examine the radiosensitizing effects of cell state transition blockade in GBM. Data generated from this grant will encompass TCGA datasets, patient derived GSCs, clinically relevant xenograft models as well as testing of inhibitors in these models with a trajectory toward Phase I clinical trials to overcome radioresistance in patients with GBM.