In this study, a folic acid-functionalized niosome was formulated and loaded with letrozole and curcumin as a promising drug carrier system for chemotherapy of the breast cancer cells. The formulation process was optimized by varying the type of Span 80 and total lipid to drug ratio, where Span 80 and lipid to drug molar ratio of 10 resulted in the niosomes with maximum encapsulation of both drugs but minimum size. The developed niosomal formulation showed a great storage stability up to one month with the small changes in drug encapsulation efficiency and size during the storage. In addition, they showed a pH-dependent release behaviour with slow drug release at physiological pH (7.4) while considerable drug release in acidic conditions (pH = 3), making it a promising candidate for breast cancer treatment. The cytotoxicity study shows the niosomal formulation has high biocompatibility with HEK-293 healthy cells, while having remarkable inhibitory effects on MCF-7 and MDA-MB-231 breast cancer cells due to the presence of folic acid in formulation, and in turn, selective internalization of the as-developed nanocarrier through folate receptor-mediated endocytosis. The double drug-loaded niosomes affect the gene expression by studied breast cancer cell lines; down-regulates the expression of Bcl2, cyclin D, and cyclin E genes while they up-regulate the expression of p53, Bax, caspase-3, and caspase-9 genes. The flow cytometry results showed that letrozole/curcumin-loaded niosomes enhanced the apoptosis rate in both MCF-7 and MDA-MB-231 cells compared to the mixture of letrozole and curcumin, which was due to the synergic effect between the two drugs as well as higher cell uptake by niosomal formulation. The findings of our study show the importance of developing highly biocompatible niosomal formulations in the future of nanomedicine that enables the co-delivery of two hydrophobic drugs into the cancer cells improves the efficiency of chemotherapy due to the synergic effect between the drugs.

在这项研究中，叶酸官能化的脂质体被配制并装载来曲唑和姜黄素作为一种有前途的用于乳腺癌细胞化学疗法的药物载体系统。通过改变Span 80的类型和总脂质与药物的比例来优化配制过程，其中Span 80和脂质与药物的摩尔比为10时，两种药物的包封量最大但尺寸最小的脂质体。所开发的脂质体配方在长达一个月的时间里显示出极好的储存稳定性，并且在储存过程中药物封装效率和尺寸的微小变化。此外，它们还显示出pH依赖性的释放行为，在生理pH值（7.4）时药物释放缓慢，而在酸性条件下（pH = 3）则释放出大量药物，这使其成为乳腺癌治疗的有希望的候选者。细胞毒性研究表明，该基因型配方与HEK-293健康细胞具有高度的生物相容性，同时由于配方中存在叶酸而对MCF-7和MDA-MB-231乳腺癌细胞具有显着的抑制作用，进而具有选择性通过叶酸受体介导的内吞作用使已开发的纳米载体内在化。载有双重药物的脂质体通过研究的乳腺癌细胞系影响基因表达。下调Bcl2，cyclin D和cyclin E基因的表达，同时上调p53，Bax，caspase-3和caspase-9基因的表达。流式细胞仪检测结果表明，与来曲唑和姜黄素的混合物相比，来曲唑/姜黄素负载的脂质体提高了MCF-7和MDA-MB-231细胞的凋亡率，这是由于两种药物之间的协同作用，以及通过基因组制剂吸收更高的细胞所致。我们研究的结果表明，在未来的纳米医学中，开发高度生物相容性的纳米脂质体制剂非常重要，因为这两种疏水性药物可以共同递送入癌细胞，由于药物之间的协同作用，因此可以提高化疗的效率。