Université Lille, Inserm, CHU Lille, U1192, Laboratoire Protéomique, Réponse Inflammatoire et Spectrométrie de Masse (PRISM), Lille, France.
Breast Cancer Unit, Oscar Lambret Center, Lille, France.
Front Immunol. 2021 Sep 27;12:746168. doi: 10.3389/fimmu.2021.746168. eCollection 2021.
Glioblastoma (GBM) is the most common and devastating malignant brain tumor in adults. The mortality rate is very high despite different treatments. New therapeutic targets are therefore highly needed. Cell-surface proteins represent attractive targets due to their accessibility, their involvement in essential signaling pathways, and their dysregulated expression in cancer. Moreover, they are potential targets for CAR-based immunotherapy or mRNA vaccine strategies. In this context, we investigated the GBM-associated surfaceome by comparing it to astrocytes cell line surfaceome to identify new specific targets for GBM. For this purpose, biotinylation of cell surface proteins has been carried out in GBM and astrocytes cell lines. Biotinylated proteins were purified on streptavidin beads and analyzed by shotgun proteomics. Cell surface proteins were identified with Cell Surface Proteins Atlas (CSPA) and Gene Ontology enrichment. Among all the surface proteins identified in the different cell lines we have confirmed the expression of 66 of these in patient's glioblastoma using spatial proteomic guided by MALDI-mass spectrometry. Moreover, 87 surface proteins overexpressed or exclusive in GBM cell lines have been identified. Among these, we found 11 specific potential targets for GBM including 5 mutated proteins such as RELL1, CYBA, EGFR, and MHC I proteins. Matching with drugs and clinical trials databases revealed that 7 proteins were druggable and under evaluation, 3 proteins have no known drug interaction yet and none of them are the mutated form of the identified proteins. Taken together, we discovered potential targets for immune therapy strategies in GBM.
胶质母细胞瘤（GBM）是成人中最常见和最具破坏性的恶性脑肿瘤。尽管采用了不同的治疗方法，但其死亡率仍然非常高。因此，非常需要新的治疗靶点。由于细胞表面蛋白具有可及性、参与重要信号通路以及在癌症中失调表达等特点，因此它们成为有吸引力的靶点。此外，它们是 CAR 为基础的免疫疗法或 mRNA 疫苗策略的潜在靶点。在这种情况下，我们通过将其与星形胶质细胞瘤细胞系的表面组进行比较，来研究与 GBM 相关的表面组，以确定 GBM 的新的特异性靶点。为此，我们在 GBM 和星形胶质细胞瘤细胞系中进行了细胞表面蛋白的生物素化。生物素化的蛋白质在链霉亲和素珠上纯化，并通过 shotgun 蛋白质组学进行分析。使用细胞表面蛋白图谱（CSPA）和基因本体论富集对细胞表面蛋白进行鉴定。在不同细胞系中鉴定的所有表面蛋白中，我们使用 MALDI-质谱引导的空间蛋白质组学方法在患者的 GBM 中验证了其中 66 种蛋白的表达。此外，还鉴定了 87 种在 GBM 细胞系中过度表达或特异表达的表面蛋白。其中，我们发现了 11 个可能成为 GBM 特异性靶标的潜在靶点，包括 5 个突变蛋白，如 RELL1、CYBA、EGFR 和 MHC I 蛋白。与药物和临床试验数据库匹配发现，有 7 种蛋白具有可药用性并正在评估中，3 种蛋白目前尚无已知的药物相互作用，且它们都不是鉴定出的蛋白的突变形式。总之，我们发现了 GBM 免疫治疗策略的潜在靶点。
