作者:Xizhe Tian、Kyung-Hwa Baek、Injae Shin
DOI:10.1039/c2sc21777e
日期:——
The currently available anticancer agents frequently cause unwanted normal cell death mainly owing to their lack of selectivity for cancer cells. In addition, molecular imaging agents for tumors exhibit low target-to-background ratios. As a consequence, elegant methods that more specifically target cancer cells need to be developed for the improvement of chemotherapeutic efficacy and diagnosis. In a recent effort aimed at improving the tumor selectivity of therapeutic and imaging agents, we designed, synthesized and explored the effectiveness of a dual-targeting delivery system that targets cancer cells more selectively. The new delivery system is composed of a synthetic ligand (octreotide) of somatostatin receptors, a dipeptide substrate for cathepsin B, and a fluorophore or an anticancer agent. The fluorophore-conjugated delivery system was found to be applicable for specific fluorescence imaging of cancer cells that express both somatostatin receptors and cathepsin B. In addition, the anticancer agent-containing delivery system leads to the death of cancer cells specifically. In contrast to cancer cells, normal cells that do not produce both somatostatin receptors and cathepsin B at high levels are unaffected by the delivery system. The new dual-targeting approach has the capability of overcoming obstacles associated with current chemotherapeutic and imaging methods.
目前可用的抗癌药物常常会导致不希望的正常细胞死亡,这主要归因于它们对癌细胞缺乏选择性。此外,针对肿瘤的分子影像剂显示出较低的靶背景比。因此,需要开发更精确地靶向癌细胞的优雅方法,以提高化学治疗效果和诊断。在最近旨在提高治疗和成像剂对肿瘤选择性的努力中,我们设计、合成了并探索了这种更选择性地靶向癌细胞的双重靶向递送系统的有效性。这种新的递送系统由生长激素抑制素受体的合成配体(奥曲肽)、组织蛋白酶B的二肽底物和氟光素或抗癌药物组成。发现氟光素耦合的递送系统可用于对表达生长激素抑制素受体和组织蛋白酶B的癌细胞进行特异性荧光成像。此外,含有抗癌药物的递送系统可特异性地导致癌细胞死亡。与癌细胞不同,不同时高水平产生生长激素抑制素受体和组织蛋白酶B的正常细胞不会受到递送系统的影响。这种新的双重靶向方法具有克服当前化疗和成像方法相关障碍的能力。