Terada Takeshi, Iwai Mieko, Kawakami Shigeru, Yamashita Fumiyoshi, Hashida Mitsuru
Department of Drug Delivery Research, Graduate School of Pharmaceutical Sciences, Kyoto University, Kyoto 606-8501, Japan.
J Control Release. 2006 Apr 10;111(3):333-42. doi: 10.1016/j.jconrel.2005.12.023. Epub 2006 Feb 20.
In order to obtain an HCC-selective drug delivery system, a novel functional lipid, which is cleaved by the protease activity of matrix metalloproteinase-2 (MMP-2), was developed. The amino group of dioleoylphosphatidylethanolamine (DOPE) was conjugated with PEGylated MMP-2 substrate peptide (Gly-Pro-Leu-Gly-Ile-Ala-Gly-Gln), and MMP-2-cleavable PEG-Peptide-DOPE (PEG-PD) was synthesized. When PEG-PD was incorporated in galactosylated liposomes (Gal-PEG-PD-liposomes), we expected that Gal-PEG-PD-liposomes would not be taken up by normal hepatocytes due to the steric hindrance effect, but would be activated around HCC cells by secreted MMPs. In the pretreatment by hMMP2 (1, 5, and 10mug/ml), an hMMP2 concentration-dependent higher uptake of Gal-PEG-PD-liposomes was observed in HepG2 cells, suggesting PEG-PD cleavage. In the presence of an excess of galactose, the uptake of Gal-PEG-PD-liposomes with hMMP2 was significantly inhibited, suggesting asialoglycoprotein receptor-mediated uptake of Gal-PEG-PD-liposomes following the PEG-PD cleavage. Pretreatment of Gal-PEG-PD-liposomes with the conditioned medium of B16BL6, which contained secreted MMPs, enhanced the binding to HepG2 cells, as in the case of hMMP-2 treatment. Moreover, the cytotoxicity of N(4)-octadecyl-1-beta-d-arabinofuranosylcytosine (NOAC) incorporated Gal-PEG-PD-liposomes was enhanced by hMMPs (5mug/ml) and its cytotoxicity was significantly reduced by the presence of an excess of galactose in HepG2 cells. In conclusion, Gal-PEG-PD-liposomes were successfully developed for novel HCC-selective targeting.
为了获得一种肝癌选择性药物递送系统，开发了一种新型功能脂质，它可被基质金属蛋白酶-2（MMP-2）的蛋白酶活性切割。将二油酰磷脂酰乙醇胺（DOPE）的氨基与聚乙二醇化的MMP-2底物肽（甘氨酸-脯氨酸-亮氨酸-甘氨酸-异亮氨酸-丙氨酸-甘氨酸-谷氨酰胺）偶联，合成了MMP-2可切割的聚乙二醇-肽-DOPE（PEG-PD）。当PEG-PD掺入半乳糖基化脂质体（Gal-PEG-PD-脂质体）中时，我们预期由于空间位阻效应，Gal-PEG-PD-脂质体不会被正常肝细胞摄取，但会在肝癌细胞周围被分泌的MMPs激活。在用hMMP2（1、5和10μg/ml）预处理时，在HepG2细胞中观察到Gal-PEG-PD-脂质体的摄取呈hMMP2浓度依赖性升高，提示PEG-PD被切割。在存在过量半乳糖的情况下，hMMP2处理的Gal-PEG-PD-脂质体的摄取显著受到抑制，提示在PEG-PD切割后，Gal-PEG-PD-脂质体通过去唾液酸糖蛋白受体介导摄取。用含有分泌型MMPs的B16BL6条件培养基预处理Gal-PEG-PD-脂质体，增强了其与HepG2细胞的结合，与hMMP-2处理的情况相同。此外，hMMPs（5μg/ml）增强了掺入Gal-PEG-PD-脂质体的N(4)-十八烷基-1-β-D-阿拉伯呋喃糖基胞嘧啶（NOAC）的细胞毒性，而在HepG2细胞中过量半乳糖的存在显著降低了其细胞毒性。总之，成功开发了Gal-PEG-PD-脂质体用于新型肝癌选择性靶向。
