Anti-cancer chemotherapy with good efficacy and fewer side effects is highly desirable. A drug delivery system comprising a cancer-targeting module and a cytotoxic agent connected with a cleavable linker is promising for reducing side effects. The development of a cleavable linker satisfying the requirements of both stability and cleavability, however, is difficult, especially when a carbonate moiety is used for conjugating the linker to a hydroxy group in a drug of interest. We herein report a new stable linker comprising carbamate and ester spacers, which can be introduced on a hydroxy group of a drug. This linker is more stable in aqueous neutral buffer than a corresponding carbonate-type linker, and releases a payload anti-cancer drug, SN-38, through a two-step sequence upon cathepsin B treatment. This linker may have potential use in other drug delivery systems to lower side effects by selectively transporting cytotoxic drugs to tumor cells.
疗效好、副作用少的抗癌化疗是非常理想的。由癌症靶向模块和细胞毒剂组成的给药系统与可裂解连接剂相连接,有望减少副作用。然而,要开发出一种同时满足稳定性和可裂解性要求的可裂解连接体并不容易,尤其是在使用
碳酸盐分子将连接体与相关药物中的羟基相连接的情况下。我们在此报告一种由
氨基甲酸酯和酯间隔物组成的新型稳定连接体,这种连接体可被引入药物的羟基上。与相应的
碳酸盐型连接体相比,这种连接体在
水性中性缓冲液中更为稳定,并能在
蛋白酶 B 处理后通过两步序列释放有效载荷抗癌药物 SN-38。这种连接体有可能用于其他药物输送系统,通过选择性地向肿瘤细胞输送细胞毒性药物来降低副作用。