Vascular Biology Program, Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, United States.
Department of Surgery, Harvard Medical School and Boston Children's Hospital, 300 Longwood Avenue, Boston, MA, 02115, United States.
Sci Rep. 2019 Apr 17;9(1):6195. doi: 10.1038/s41598-019-42643-7.
High grade gliomas, including glioblastoma (GBM), are the most common and deadly brain cancers in adults. Here, we performed a quantitative and unbiased screening of 70 cancer-related antigens using comparative flow cytometry and, for the first time, identified integrin alpha-2 (ITGA2) as a novel molecular target for GBM. In comparison to epidermal growth factor receptor (EGFR), a well-established GBM target, ITGA2 is significantly more expressed on human GBM cells and significantly less expressed on normal human glial cells. We also found that ITGA2 antibody blockade significantly impedes GBM cell migration but not GBM cell proliferation. To investigate the utility of ITGA2 as a therapeutic target in GBM, we designed and engineered an ITGA2 antibody-directed liposome that can selectively deliver doxorubicin, a standard-of-care chemotherapeutic agent, to GBM cells. This novel approach significantly improved antitumor efficacy. We also demonstrated that these ITGA2 antibody-directed liposomes can effectively breach the blood-brain tumor barrier (BBTB) in vitro via GBM-induced angiogenesis effects. These findings support further research into the use of ITGA2 as a novel nanotherapeutic target for GBM.
高级别神经胶质瘤,包括胶质母细胞瘤(GBM),是成人中最常见和最致命的脑癌。在这里,我们使用比较流式细胞术对 70 种与癌症相关的抗原进行了定量和无偏筛选,首次发现整合素 alpha-2(ITGA2)是 GBM 的一个新的分子靶标。与已确立的 GBM 靶标表皮生长因子受体(EGFR)相比,ITGA2 在人 GBM 细胞上的表达显著更高,而在正常的人类神经胶质细胞上的表达显著更低。我们还发现,ITGA2 抗体阻断显著阻碍 GBM 细胞迁移,但不影响 GBM 细胞增殖。为了研究 ITGA2 作为 GBM 的治疗靶标的效用,我们设计并构建了一种 ITGA2 抗体导向的脂质体,该脂质体可以将阿霉素(一种标准的化疗药物)选择性递送至 GBM 细胞。这种新方法显著提高了抗肿瘤疗效。我们还证明,这些 ITGA2 抗体导向的脂质体可以通过 GBM 诱导的血管生成作用,有效地穿透体外血脑肿瘤屏障(BBTB)。这些发现支持进一步研究将 ITGA2 用作 GBM 的新型纳米治疗靶标。