Vakili-Ghartavol Roghayyeh, Mehrabian Amin, Mirzavi Farshad, Rezayat Seyed Mahdi, Mashreghi Mohammad, Farhoudi Leila, Kharrazi Sharmin, Sadri Kayvan, Jaafari Mahmoud Reza
Department of Medical Nanotechnology, School of Advanced Medical Sciences and Technologies, Shiraz University of Medical Sciences, Shiraz, Iran.
Department of Medical Nanotechnology, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran.
J Pharm Pharmacol. 2022 Sep 1;74(9):1307-1319. doi: 10.1093/jpp/rgac048.
Metformin has been shown to kill cancer stem-like cells in genetically various types of breast carcinoma. With the aim to simultaneously eradicate the bulk population of tumour cells and the rare population of cancer stem-like cells in breast cancer tissues, we used the combination chemotherapy of docetaxel (DTX) with metformin (MET). Furthermore, we introduce an active loading method based on ammonium sulphate 250 mM (SA) for encapsulating docetaxel into liposomes.
Docetaxel and metformin encapsulated into PEGylated liposomes with two different methods based on remote or passive loading methods, respectively. The size and surface charge of the liposomes were characterized. DTX content in the nanoliposomes was measured by the high-performance liquid chromatography method. The drug release profiles were evaluated in phosphate-buffered dextrose 5% with the pH of 6.5 and 7.4. We examined the antitumour activity of Taxotere (TAX), and liposomal formulation of DTX and MET as a monotherapy or combination therapy. The biodistribution of liposomes was also investigated using 99mTc hexamethyl propylene amine oxime method in BALB/c mice bearing 4T1 breast carcinoma tumours.
The final formulations were prepared according to the best physicochemical characteristics which were HSPC/mPEG2000-DSPE/Chol (DTX liposomes) and HSPC/DPPG/mPEG2000-DSPE/Chol (MET liposomes), at molar ratios of 85/5/10 and (55/5/5/35), respectively. In vivo experiments showed that when free or liposomal metformin used in combination with liposomal docetaxel, they prolonged median survival time (MST) from 31 in the control group to 46 days, which demonstrates their promising effects on the survival of the 4T1 breast carcinoma mice models. Moreover, combination therapies could significantly increase life span in comparison with phosphate-buffered saline (PBS) and Taxotere groups at the same dose. Furthermore, in the combination therapy study, treatment with DTX liposomes prepared by ammonium sulphate 250 mM buffer alone resulted in similar therapeutic efficacy to combination therapy. The biodistribution study exhibited significant accumulation of DTX liposomes in the tumours due to the Enhanced Permeability and Retention effect.
This study also showed that metformin-based combinatorial chemotherapies have superior efficacy versus their corresponding monotherapy counterparts at same doses. The findings confirm that liposomes based on ammonium sulphate 250 mM could be as a promising formulation for efficient DTX delivering and cancer targeting and therefore merit further investigations.
已证明二甲双胍可杀死基因类型各异的乳腺癌中的癌症干细胞样细胞。为了同时根除乳腺癌组织中的大量肿瘤细胞和罕见的癌症干细胞样细胞群体，我们采用了多西他赛（DTX）与二甲双胍（MET）联合化疗。此外，我们引入了一种基于250 mM硫酸铵（SA）的主动装载方法，用于将多西他赛封装到脂质体中。
分别基于远程或被动装载方法，用两种不同方法将多西他赛和二甲双胍封装到聚乙二醇化脂质体中。对脂质体的大小和表面电荷进行了表征。通过高效液相色谱法测量纳米脂质体中的DTX含量。在pH值为6.5和7.4的5%磷酸缓冲葡萄糖中评估药物释放曲线。我们研究了泰索帝（TAX）、DTX和MET的脂质体制剂作为单一疗法或联合疗法的抗肿瘤活性。还使用99mTc六甲基丙烯胺肟法在携带4T1乳腺癌肿瘤的BALB/c小鼠中研究了脂质体的生物分布。
最终制剂是根据最佳理化特性制备的，分别为HSPC/mPEG2000-DSPE/Chol（DTX脂质体）和HSPC/DPPG/mPEG2000-DSPE/Chol（MET脂质体），摩尔比分别为85/5/10和（55/5/5/35）。体内实验表明，当游离或脂质体形式的二甲双胍与脂质体多西他赛联合使用时，它们将中位生存时间（MST）从对照组的31天延长至46天，这表明它们对4T1乳腺癌小鼠模型的生存具有显著效果。此外，与相同剂量的磷酸盐缓冲盐水（PBS）和泰索帝组相比，联合疗法可显著延长生存期。此外，在联合疗法研究中，仅用250 mM硫酸铵缓冲液制备的DTX脂质体治疗产生的疗效与联合疗法相似。生物分布研究显示，由于增强的渗透和滞留效应，DTX脂质体在肿瘤中显著蓄积。
本研究还表明，基于二甲双胍的联合化疗在相同剂量下比相应的单一疗法具有更高的疗效。研究结果证实，基于250 mM硫酸铵的脂质体可能是一种有前景的制剂，可用于高效递送DTX和靶向癌症，因此值得进一步研究。
