Glioblastoma (GBM) responses to bevacizumab are invariably transient with acquired resistance. We profiled paired patient specimens and bevacizumab-resistant xenograft models pre- and post-resistance toward the primary goal of identifying regulators whose targeting could prolong the therapeutic window, and the secondary goal of identifying biomarkers of therapeutic window closure. Bevacizumab-resistant patient specimens and xenografts exhibited decreased vessel density and increased hypoxia versus pre-resistance, suggesting that resistance occurs despite effective therapeutic devascularization. Microarray analysis revealed upregulated mesenchymal genes in resistant tumors correlating with bevacizumab treatment duration and causing three changes enabling resistant tumor growth in hypoxia. First, perivascular invasiveness along remaining blood vessels, which co-opts vessels in a VEGF-independent and neoangiogenesis-independent manner, was upregulated in novel biomimetic 3D bioengineered platforms modeling the bevacizumab-resistant microenvironment. Second, tumor-initiating stem cells housed in the perivascular niche close to remaining blood vessels were enriched. Third, metabolic reprogramming assessed through real-time bioenergetic measurement and metabolomics upregulated glycolysis and suppressed oxidative phosphorylation. Single-cell sequencing of bevacizumab-resistant patient GBMs confirmed upregulated mesenchymal genes, particularly glycoprotein YKL-40 and transcription factor ZEB1, in later clones, implicating these changes as treatment-induced. Serum YKL-40 was elevated in bevacizumab-resistant versus bevacizumab-naïve patients. CRISPR and pharmacologic targeting of ZEB1 with honokiol reversed the mesenchymal gene expression and associated stem cell, invasion, and metabolic changes defining resistance. Honokiol caused greater cell death in bevacizumab-resistant than bevacizumab-responsive tumor cells, with surviving cells losing mesenchymal morphology. Employing YKL-40 as a resistance biomarker and ZEB1 as a target to prevent resistance could fulfill the promise of antiangiogenic therapy. SIGNIFICANCE: Bevacizumab resistance in GBM is associated with mesenchymal/glycolytic shifts involving YKL-40 and ZEB1. Targeting ZEB1 reduces bevacizumab-resistant GBM phenotypes. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/7/1498/F1.large.jpg.

中文翻译：

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克隆ZEB1驱动的间充质转化促进靶向肿瘤抗血管生成治疗的耐药性。

胶质母细胞瘤（GBM）对贝伐单抗的反应总是短暂的，获得性耐药。我们分析了成对的患者标本和抗贝伐单抗的异种移植模型的抗药性，其主要目的是确定可延长治疗窗的调节剂的主要目标，以及确定治疗窗关闭的生物标志物的主要目标。抵抗贝伐单抗的患者标本和异种移植物相对于抗药性显示降低的血管密度和缺氧增加，表明尽管进行了有效的治疗性血运重建，抗药性仍然发生。基因芯片分析显示耐药性肿瘤中的间充质基因上调，与贝伐单抗治疗持续时间相关，并引起三种变化，使缺氧中的耐药性肿瘤生长。第一，在模拟贝伐单抗耐药的微环境的新型仿生3D生物工程平台中，沿剩余血管的血管周围浸润性（以VEGF独立和新血管生成独立的方式共同选择血管）被上调。第二，富集在靠近剩余血管的血管周围壁iche中的肿瘤起始干细胞被富集。第三，通过实时生物能测量和代谢组学评估代谢重编程上调了糖酵解和抑制了氧化磷酸化。抵抗贝伐单抗的患者GBM的单细胞测序证实了后来克隆中的间充质基因，特别是糖蛋白YKL-40和转录因子ZEB1上调，暗示这些变化是由治疗引起的。与未接受贝伐单抗的患者相比，血清YKL-40升高。使用厚朴酚的CRISPR和ZEB1药理靶向可逆转间充质基因表达以及相关的干细胞，侵袭和代谢变化，从而确定耐药性。厚朴酚在耐药性贝伐单抗中比在贝伐单抗反应性中引起更大的细胞死亡，存活的细胞失去间充质形态。以YKL-40作为抗药性生物标志物和ZEB1作为预防抗药性的靶标可实现抗血管生成治疗的希望。意义：GBM中的贝伐单抗耐药与涉及YKL-40和ZEB1的间充质/糖酵解转变有关。靶向ZEB1可降低抗贝伐单抗的GBM表型。图形摘要：http://cancerres.aacrjournals.org/content/canres/80/7/1498/F1.large.jpg。