Exploiting cell fate transition to overcome radiation resistance in glioblastoma

项目总结 胶质母细胞瘤(GBM)是一种毁灭性的脑瘤，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，肾小球基底膜瘤仍无法治愈。GBM是出了名的辐射 抵抗力强。通过对患者肿瘤的基因组分析进行GBM的分子亚型鉴定出三个主要亚型， 根据基因表达模式，称为神经性(PN)，经典型或间充质(MES)。协作性 苏尔曼实验室和哈特实验室多年来的努力已经发现了胶质瘤干细胞(GSCs)。 与GBM的分子亚型非常相似。然而，这些状态显示出可塑性，我们开创了 PN到MES过渡的概念基于使用患者来源的GSC将MES信号与无线电联系起来的研究- 抗性和鉴定与MES亚型相关的主要转录因子。新的令人兴奋的 来自我们实验室的初步数据已经确定了三个独立的分子靶点 耐辐射。利用全基因组CRISPR筛选识别与增强相关的基因靶点 辐射诱导蛋白质复合体的辐射敏感性和质谱学评价 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，可以作为靶点 以克服GSCs的辐射抗性。这项提案的总体目标是将这些可用药的目标结合起来 标准使用分次光子放射治疗(RT)并将GSCs从抗辐射转换为 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 通过代谢重编程使基底膜从MES状态转变为PN状态的放射增敏作用。在目标2中，我们将 测试目标高迁移组框2(HMGB2)是否会导致MES块过渡和更改 染色质，以及它是否与辐射相结合是致命的。最后，在目标3中，我们将检查放射增敏 联合应用TAZ抑制剂和电离辐射对慢性髓细胞白血病临床前模型神经元分化的影响 GBM。我们的建议意义重大，因为这是第一项全面研究辐射增敏作用的研究。 细胞状态转换阻断在基底膜中的作用。从该赠款产生的数据将包括TCGA数据集， 患者来源的GSCs、临床相关的异种移植模型以及这些模型中的抑制剂测试 为克服GBM患者的辐射抵抗而进行的I期临床试验。

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.