Therapeutically targeting glypican-2 via single-domain antibody-based chimeric antigen receptors and immunotoxins in neuroblastoma
Therapeutically targeting glypican-2 via single-domain antibody-based chimeric antigen receptors and immunotoxins in neuroblastoma
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DOI：
10.1073/pnas.1706055114
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发表时间：
2017-08-08
影响因子：
11.1
通讯作者：
Ho, Mitchell
中科院分区：
文献类型：
--
作者：
Li, Nan;Fu, Haiying;Ho, Mitchell
神经母细胞瘤是一种儿童癌症，尽管进行了密集的多模态治疗，但几乎一半的患者仍是致命的。这种癌症来源于位于交感神经系统的神经内分泌组织。磷脂酰肌醇蛋白聚糖-2（GPC 2）是一种细胞表面硫酸乙酰肝素蛋白聚糖，对神经细胞粘附和神经突生长非常重要。在这项研究中，我们发现GPC 2蛋白在大约一半的神经母细胞瘤病例中高度表达，并且与GPC 2低表达的患者相比，GPC 2高表达与总生存率低相关。我们证明了通过CRISPR-Cas9或siRNA沉默GPC 2导致神经母细胞瘤肿瘤细胞生长的抑制。GPC 2沉默使Wnt/β-连环蛋白信号转导失活，并降低靶基因N-Myc的表达，N-Myc是神经母细胞瘤肿瘤发生的致癌驱动因子。我们已经通过噬菌体展示技术分离了对GPC 2具有特异性的人单域抗体，并且发现单域抗体可以通过破坏GPC 2和Wnt 3a的相互作用来抑制活性β-连环蛋白信号传导。为了探索GPC 2作为神经母细胞瘤的潜在靶点，我们开发了两种形式的抗体治疗剂，免疫毒素和嵌合抗原受体（CAR）T细胞。免疫毒素治疗被证明可以抑制小鼠神经母细胞瘤的生长。靶向GPC 2的CAR T细胞消除了播散性神经母细胞瘤小鼠模型中的肿瘤，其中肿瘤转移已经扩散到多个临床相关部位，包括脊柱、颅骨、腿部和骨盆。这项研究表明，GPC 2作为一个有前途的治疗靶点在神经母细胞瘤。
Neuroblastoma is a childhood cancer that is fatal in almost half of patients despite intense multimodality treatment. This cancer is derived from neuroendocrine tissue located in the sympathetic nervous system. Glypican-2 (GPC2) is a cell surface heparan sulfate proteoglycan that is important for neuronal cell adhesion and neurite outgrowth. In this study, we find that GPC2 protein is highly expressed in about half of neuroblastoma cases and that high GPC2 expression correlates with poor overall survival compared with patients with low GPC2 expression. We demonstrate that silencing of GPC2 by CRISPR-Cas9 or siRNA results in the inhibition of neuroblastoma tumor cell growth. GPC2 silencing inactivates Wnt/beta-catenin signaling and reduces the expression of the target gene N-Myc, an oncogenic driver of neuroblastoma tumorigenesis. We have isolated human single-domain antibodies specific for GPC2 by phage display technology and found that the single-domain antibodies can inhibit active beta-catenin signaling by disrupting the interaction of GPC2 and Wnt3a. To explore GPC2 as a potential target in neuroblastoma, we have developed two forms of antibody therapeutics, immunotoxins and chimeric antigen receptor (CAR) T cells. Immunotoxin treatment was demonstrated to inhibit neuroblastoma growth in mice. CAR T cells targeting GPC2 eliminated tumors in a disseminated neuroblastoma mouse model where tumor metastasis had spread to multiple clinically relevant sites, including spine, skull, legs, and pelvis. This study suggests GPC2 as a promising therapeutic target in neuroblastoma.