Controlled release of free doxorubicin from peptide-drug conjugates by drug loading
Controlled release of free doxorubicin from peptide-drug conjugates by drug loading
复制标题
DOI：
10.1016/j.jconrel.2014.05.051
复制
发表时间：
2014-10-10
影响因子：
10.8
通讯作者：
Cui, Honggang
中科院分区：
文献类型：
--
作者：
Chen, Zhipeng;Zhang, Pengcheng;Cui, Honggang
利用多肽对药物进行共价修饰已被广泛应用于改善药物疗效的有效策略。设计这种前药的一个重要考虑因素是以期望的方式将游离药物从共价结合形式释放出来。在大多数情况下，游离药物的释放速率由各种化学连接物的使用来控制，这些化学连接物将药物连接到辅助片段。我们在这里报道，除了对所得到的结合物的载药量有明显的影响外，每个多肽的药物结合度也可以调节药物的释放。在这项工作中，我们合成了三种多肽-药物结合物(NTD，d-NTD和Q-NTD)，其中穿细胞肽TAT通过组织蛋白酶B可降解的四肽连接物(-Gly-Phe-Leu-Gly-)分别与一个、两个或四个阿霉素共价连接。我们发现阿霉素结合物中阿霉素的数量对阿霉素的释放有显著的影响，其中Q-NTD的释放速度最慢，而NTD的释放速度最快。我们的细胞摄取实验表明，Q-NTD在癌细胞内的累积最有效，而NTD在细胞内的累积浓度最低。有趣的是，我们使用SRB实验进行的细胞活性评估显示，d-NTD是对人肝癌细胞最有效的偶联物。这些结果表明，细胞内蓄积效率和药物释放速率是决定药物结合物体外药效的两个重要因素。为了进一步验证这一结论，我们将一种短烃结合到NTD上以提高其细胞摄取，并发现所得到的结合物C16NTD具有与Q-NTD结合物相似的细胞内积累，但由于其更有效地释放游离阿霉素而具有更好的抗癌活性。(C)2014爱思唯尔B.V.保留所有权利。
Covalent modification of a drug with a peptide moiety has been extensively used as an effective strategy to improve the drug's therapeutic outcome. One important consideration in the design of such a prodrug is the release of the free drug from the covalently bound form in a desired fashion. In most cases, the free drug release rate is controlled by the use of various chemical linkers that bridge the drug to the auxiliary segment. We report here that the degree of drug conjugation per peptide could also regulate the drug release in addition to its apparent effect on drug loading of the resulting conjugates. In this work, we synthesized three peptide-drug conjugates (NTD, d-NTD and q-NTD) in which the cell penetrating peptide Tat is covalently connected to one, two, or four doxorubicin, respectively, through a cathepsin B degradable tetrapeptide linker (-Gly-Phe-Leu-Gly-). We found that the number of doxorubicin within the conjugate impacts the release of doxorubicin in a significant way, with q-NTD showing the slowest release rate while NTD showing the fastest release rate. Our cellular uptake experiments reveal that q-NTD accumulated most effectively within cancer cells while NTD shows the lowest intracellular accumulation concentration. Interestingly, our cell viability assessment using a SRB assay reveals that d-NTD is the most potent conjugate against HepG2 human liver cancer cells. These results suggest that intracellular accumulation efficiency and the free drug release rate are two important factors that determine the in vitro efficacy of drug conjugates. To further validate this conclusion, we conjugated a short hydrocarbon onto the NTD to improve its cellular uptake, and found that the resulting conjugate, C16NTD, exhibited comparable intracellular accumulation as the q-NTD conjugate but superior anticancer activity due to its more effective release of free doxorubicin. (C) 2014 Elsevier B.V. All rights reserved.