Pedrini Isabella, Gazzano Elena, Chegaev Konstantin, Rolando Barbara, Marengo Alessandro, Kopecka Joanna, Fruttero Roberta, Ghigo Dario, Arpicco Silvia, Riganti Chiara
Department of Drug Science and Technology, University of Torino , via Pietro Giuria 9, 10125 Torino, Italy.
Mol Pharm. 2014 Sep 2;11(9):3068-79. doi: 10.1021/mp500257s. Epub 2014 Jul 30.
In this work we prepared and characterized two liposomal formulations of a semisynthetic nitric oxide (NO)-releasing doxorubicin (Dox), called nitrooxy-Dox (NitDox), which we previously demonstrated to be cytotoxic in Dox-resistant human colon cancer cells. Liposomes with 38.2% (Lip A) and 19.1% (Lip B) cholesterol were synthesized: both formulations had similar size and zeta potential values and caused the same intracellular distribution of free NitDox, but Lip B accumulated and released NitDox more efficiently. In Dox-resistant human colon cancer cells, Lip A and Lip B exhibited a more favorable kinetics of drug uptake and NO release, and a stronger cytotoxicity than Dox and free NitDox. While Caelyx, one of the liposomal Dox formulations approved for breast and ovary tumors treatment, was ineffective in Dox-resistant breast/ovary cancer cells, Lip B, and to a lesser extent Lip A, still exerted a significant cytotoxicity in these cells. This event was accompanied in parallel by a higher release of NO, which caused nitration of P-glycoprotein (Pgp) and multidrug resistance related protein 1 (MRP1), two transporters involved in Dox efflux, and impaired their pump activity. By doing so, the efflux kinetics of Dox after treatment with Lip B was markedly slowed down and the intracellular accumulation of Dox was increased in breast and ovary drug-resistant cells. We propose these liposomal formulations of NitDox as new tools with a specific indication for tumors overexpressing Pgp and MRP1.
在本研究中，我们制备并表征了两种半合成一氧化氮（NO）释放型阿霉素（Dox）的脂质体制剂，称为硝基氧代阿霉素（NitDox），我们之前已证明其对阿霉素耐药的人结肠癌细胞具有细胞毒性。合成了胆固醇含量分别为38.2%（脂质体A）和19.1%（脂质体B）的脂质体：两种制剂具有相似的尺寸和zeta电位值，并导致游离NitDox在细胞内的分布相同，但脂质体B积累和释放NitDox的效率更高。在阿霉素耐药的人结肠癌细胞中，脂质体A和脂质体B表现出更有利的药物摄取和NO释放动力学，并且比阿霉素和游离NitDox具有更强的细胞毒性。虽然Caelyx是一种被批准用于治疗乳腺癌和卵巢癌的脂质体阿霉素制剂之一，但在阿霉素耐药的乳腺癌/卵巢癌细胞中无效，而脂质体B，以及程度较轻的脂质体A，在这些细胞中仍具有显著的细胞毒性。这一事件同时伴随着更高的NO释放，这导致参与阿霉素外排的两种转运蛋白——P-糖蛋白（Pgp）和多药耐药相关蛋白1（MRP1）发生硝化，并损害了它们的泵活性。通过这样做，脂质体B处理后阿霉素的外排动力学明显减慢，并且在乳腺癌和卵巢癌耐药细胞中阿霉素的细胞内积累增加。我们提出这些NitDox脂质体制剂作为针对过表达Pgp和MRP1的肿瘤的具有特定适应症的新工具。
