Intratumoral spatial heterogeneity of BTK kinomic activity dictates distinct therapeutic response within a single glioblastoma tumor.
Intratumoral spatial heterogeneity of BTK kinomic activity dictates distinct therapeutic response within a single glioblastoma tumor.
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DOI：
10.3171/2019.7.jns191376
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发表时间：
2020-12-01
影响因子：
4.1
通讯作者：
Nakano I
中科院分区：
文献类型：
--
作者：
Ibrahim AN;Yamashita D;Anderson JC;Abdelrashid M;Alwakeal A;Estevez-Ordonez D;Komarova S;Markert JM;Goidts V;Willey CD;Nakano I
尽管最近通过探索胶质母细胞瘤(GBM)的基因组和转录组来开发有效的治疗方法做出了重大努力，但治疗策略仍然非常难以捉摸。因此，迫切需要新的有效的治疗方法。在这项研究中，作者试图从以前未被充分利用的方法(即空间异质性)中探索GBM的运动学图景，然后根据这一基于运动学的逐步新方法验证Bruton的酪氨酸激酶(BTK)靶向。从2例GBM患者中获得12例GBM肿瘤标本，并进行组织病理学观察。对这些组织进行PamStation多肽阵列分析，以测量每个样本的运动学活性。然后利用Ivy GBM数据库通过研究BTK相关转录因子(TF)在肿瘤中的表达来确定BTK活性在肿瘤内的空间定位。通过慢病毒短发夹状RNA(ShRNA)敲除BTK家族成员，以确定其在核心样和边缘样GBM神经球模型中的功能。最后，正在进行非脑肿瘤临床研究的BTK小分子抑制剂ONO/GS-4059被应用于对新建立的区域性特定的GBM边缘和核心神经球模型的药理抑制。运动学研究发现，这两个患者的GBM组织有两个主要的亚群，表现出不同的激酶活性特征。相反，在这些空间定义的亚群中，BTK是差异表达的中心激酶。根据Ivy GBM数据库，与BTK相关的转录因子在肿瘤核心部位高表达，但在边缘部位不表达。短发夹状RNA介导的BTK基因沉默在先前建立的边缘和核心状GBM神经球中显示出更高的凋亡活性，与边缘样神经球相比，核心样神经球的亚G1期占优势。最后，ONO/GS-4059对BTK的药理抑制导致了区域来源的GBM核心细胞的生长抑制，在较小程度上也抑制了边缘细胞的生长。这项研究发现，在不同的GBM肿瘤内和不同的不同的GBM肿瘤之间，激酶活性具有显著的异质性。研究结果表明，BTK活性在经典治疗耐药的GBM肿瘤核心中升高。鉴于这些发现，通过BTK靶向GBM的耐药核心可能会为GBM患者提供治疗益处。
Despite significant recent efforts applied toward the development of efficacious therapies for glioblastoma (GBM) through exploration of GBM’s genome and transcriptome, curative therapeutic strategies remain highly elusive. As such, novel and effective therapeutics are urgently required. In this study, the authors sought to explore the kinomic landscape of GBM from a previously underutilized approach (i.e., spatial heterogeneity), followed by validation of Bruton’s tyrosine kinase (BTK) targeting according to this stepwise kinomic-based novel approach. Twelve GBM tumor samples were obtained and characterized histopathologically from 2 patients with GBM. PamStation peptide-array analysis of these tissues was performed to measure the kinomic activity of each sample. The Ivy GBM database was then utilized to determine the intratumoral spatial localization of BTK activity by investigating the expression of BTK-related transcription factors (TFs) within tumors. Genetic inhibition of BTK family members through lentiviral short hairpin RNA (shRNA) knockdown was performed to determine their function in the core-like and edge-like GBM neurosphere models. Finally, the small-molecule inhibitor of BTK, ONO/GS-4059, which is currently under clinical investigation in nonbrain cancers, was applied for pharmacological inhibition of regionally specified newly established GBM edge and core neurosphere models. Kinomic investigation identified two major subclusters of GBM tissues from both patients exhibiting distinct profiles of kinase activity. Comparatively, in these spatially defined subgroups, BTK was the centric kinase differentially expressed. According to the Ivy GBM database, BTK-related TFs were highly expressed in the tumor core, but not in edge counterparts. Short hairpin RNA-mediated gene silencing of BTK in previously established edge- and core-like GBM neurospheres demonstrated increased apoptotic activity with predominance of the sub-G1 phase of core-like neurospheres compared to edge-like neurospheres. Lastly, pharmacological inhibition of BTK by ONO/GS-4059 resulted in growth inhibition of regionally derived GBM core cells and, to a lesser extent, their edge counterparts. This study identifies significant heterogeneity in kinase activity both within and across distinct GBM tumors. The study findings indicate that BTK activity is elevated in the classically therapy-resistant GBM tumor core. Given these findings, targeting GBM’s resistant core through BTK may potentially provide therapeutic benefit for patients with GBM.