Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire.
Norris Cotton Cancer Center, Dartmouth, Hanover, New Hampshire.
Neuro Oncol. 2018 Feb 19;20(3):332-342. doi: 10.1093/neuonc/nox129.
Mouse models of glioblastoma (GBM), the most aggressive primary brain tumor, are critical for understanding GBM pathology and can contribute to the preclinical evaluation of therapeutic agents. Platelet-derived growth factor (PDGF) signaling has been implicated in the development and pathogenesis of GBM, specifically the proneural subtype. Although multiple mouse models of PDGF-driven glioma have been described, they require transgenic mice engineered to activate PDGF signaling and/or impair tumor suppressor genes and typically represent lower-grade glioma.
We designed recombinant lentiviruses expressing both PDGFB and a short hairpin RNA targeting Cdkn2a to induce gliomagenesis following stereotactic injection into the dentate gyrus of adult immunocompetent mice. We engineered these viruses to coexpress CreERT2 with PDGFB, allowing for deletion of floxed genes specifically in transduced cells, and designed another version of this recombinant lentivirus in which enhanced green fluorescent protein was coexpressed with PDGFB and CreERT2 to visualize transduced cells.
The dentate gyrus of injected mice showed hypercellularity one week post-injection and subsequently developed bona fide tumors with the pathologic hallmarks of GBM leading to a median survival of 77 days post-injection. Transcriptomic analysis of these tumors revealed a proneural gene expression signature.
Informed by the genetic alterations observed in human GBM, we engineered a novel mouse model of proneural GBM. While reflecting many of the advantages of transgenic mice, this model allows for the facile in vivo testing of gene function in tumor cells and makes possible the rapid production of large numbers of immunocompetent tumor-bearing mice for preclinical testing of therapeutics.
胶质母细胞瘤（GBM）是最具侵袭性的原发性脑肿瘤，其小鼠模型对于理解 GBM 病理学具有重要意义，并有助于治疗药物的临床前评估。血小板衍生生长因子（PDGF）信号在 GBM 的发生和发病机制中起作用，特别是在神经前体亚型中。尽管已经描述了多种 PDGF 驱动的神经胶质瘤小鼠模型，但它们需要经过基因工程改造的转基因小鼠来激活 PDGF 信号和/或破坏肿瘤抑制基因，并且通常代表低级别神经胶质瘤。
我们设计了表达 PDGFB 和针对 Cdkn2a 的短发夹 RNA 的重组慢病毒，通过立体定向注射到成年免疫活性小鼠的齿状回中诱导神经胶质瘤发生。我们设计这些病毒共表达 CreERT2 与 PDGFB，允许在转导细胞中特异性删除 floxed 基因，并设计了另一种版本的重组慢病毒，其中增强型绿色荧光蛋白与 PDGFB 和 CreERT2 共表达，以可视化转导细胞。
注射后一周，注射小鼠的齿状回出现细胞增生，随后发展为具有 GBM 病理特征的真正肿瘤，导致注射后中位生存期为 77 天。这些肿瘤的转录组分析显示出神经前体细胞的基因表达特征。
根据人类 GBM 中观察到的遗传改变，我们设计了一种新的神经前体细胞 GBM 小鼠模型。虽然该模型反映了转基因小鼠的许多优势，但它允许在体内方便地测试肿瘤细胞中基因功能，并有可能快速生产大量免疫活性肿瘤携带小鼠，用于治疗药物的临床前测试。
