Key Laboratory of Functional Dairy, College of Food Science and Nutritional Engineering, China Agricultural University, PO Box 287, No. 17 Qinghua East Road, Haidian, Beijing 100083, China.
Biochimie. 2013 Feb;95(2):251-7. doi: 10.1016/j.biochi.2012.09.020. Epub 2012 Sep 23.
siRNA is promising in anti-tumor therapy. The main challenge is lack of tumor-specific intracellular delivery. In this study, a 6 amino acids peptide (A1) with high affinity for vascular endothelial growth factor receptor-1 (VEGFR1) was conjugated with a cell penetrating peptide (CPP) TAT to form a tumor-selective CPP. To evaluate the tumor-targeted penetrate property of TAT-A1, the uptake of TAT-A1 was measured by flow cytometry. The selectivity in vitro was tested in co-cultured tumor cells and normal cells by laser confocal microscope. The internalization efficiency of TAT-A1 was significantly higher than that of TAT (p < 0.05). TAT-A1 penetrated into tumor cells selectively when added to co-cultured tumor cells and normal cells due to the recognition of VEGFR1 which is over-expressed on tumor cells. Furthermore, siRNA was successfully transferred by TAT-A1 into tumor cells in a similar way of Lipofectamine 2000, which was proved to be an efficient vector. The knockout effect of siRNA transferred by TAT-A1 was obtained at both mRNA and protein level. These results indicated that the tumor-targeted TAT-A1 can act as an excellent vehicle for specific delivery of anti-cancer agents.
siRNA 在抗肿瘤治疗中很有前景。主要挑战是缺乏肿瘤特异性的细胞内递药。在这项研究中，一种与血管内皮生长因子受体-1（VEGFR1）具有高亲和力的 6 个氨基酸肽（A1）与细胞穿透肽（CPP）TAT 缀合，形成肿瘤选择性 CPP。为了评估 TAT-A1 的肿瘤靶向穿透特性，通过流式细胞术测量 TAT-A1 的摄取。通过激光共聚焦显微镜在共培养的肿瘤细胞和正常细胞中测试体外选择性。与 TAT 相比，TAT-A1 的内化效率明显更高（p<0.05）。由于在肿瘤细胞上过表达的 VEGFR1 的识别，TAT-A1 可以选择性地进入共培养的肿瘤细胞和正常细胞中的肿瘤细胞。此外，siRNA 被成功地通过 TAT-A1 以类似于 Lipofectamine 2000 的方式转染到肿瘤细胞中，这被证明是一种有效的载体。TAT-A1 转染的 siRNA 在 mRNA 和蛋白水平上都获得了敲除效果。这些结果表明，肿瘤靶向 TAT-A1 可以作为一种优秀的载体，用于特异性递抗癌药物。
