Department of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, University of Utah, 30 S 2000 E, Salt Lake City, UT 84112, USA.
Department of Pharmaceutics and Pharmaceutical Chemistry, College of Pharmacy, University of Utah, 30 S 2000 E, Salt Lake City, UT 84112, USA.
Int J Pharm. 2022 Apr 5;617:121589. doi: 10.1016/j.ijpharm.2022.121589. Epub 2022 Feb 14.
Bile acid transporter-targeting has been proven to be an effective strategy to improve drug delivery to hepatocytes and enterocytes. With increasing discoveries of bile acid transporter expression on tumor cells, bile acid-modified anticancer drugs are gradually attaining interests. In our previous study, we confirmed the efficacy of glycocholic acid-conjugated polystyrene nanoparticles (GCPN) on apical sodium bile acid transporter (ASBT)-expressed SK-BR-3 cells. However, the transport mechanisms remain unknown, due to the nanosized carriers are unlikely to be pumped through the narrow cavities of ASBT. To clarify their transport pathways, in this article, pharmacological inhibition and gene knocking-down studies were performed, which revealed that GCPN were primarily internalized via non-caveolar lipid raft-mediated endocytosis. Proteomics was analyzed to explore the in-depth mechanisms. In total 561 proteins were identified and statistical overrepresentation test was used to analyze the gene ontology (GO) upregulated pathways based on the highly expressed proteins. It was found that multiple pathways were upregulated and might coordinate to assist the location of the GCPN-ASBT complex and the recycling of ASBT. Among the highly expressed proteins, myelin and lymphocyte protein 2 (MAL2) was selected and confirmed to colocalize with GCPN, which further supported the lipid raft-mediated process. These findings will help set up a platform for designing the bile acid-modified nanomedicines and regulating their transport to improve their anticancer efficacy.
胆汁酸转运体靶向已被证明是一种有效的策略，可以提高药物向肝细胞和肠细胞的递送。随着越来越多的发现肿瘤细胞上胆汁酸转运体的表达，胆汁酸修饰的抗癌药物逐渐受到关注。在我们之前的研究中，我们证实了甘氨胆酸修饰的聚苯乙烯纳米粒子（GCPN）对表达顶膜钠依赖性胆汁酸转运体（ASBT）的 SK-BR-3 细胞的疗效。然而，由于纳米载体不太可能通过 ASBT 的狭窄腔被泵出，因此其转运机制仍不清楚。为了阐明它们的转运途径，在本文中进行了药理学抑制和基因敲低研究，结果表明 GCPN 主要通过非网格蛋白脂筏介导的内吞作用被内化。通过蛋白质组学分析来探讨深入的机制。共鉴定出 561 种蛋白质，并使用统计过度表达测试基于高表达蛋白分析基因本体论（GO）上调途径。发现多个途径被上调，可能协调协助 GCPN-ASBT 复合物的定位和 ASBT 的循环。在高表达的蛋白质中，选择并证实髓鞘和淋巴细胞蛋白 2（MAL2）与 GCPN 共定位，这进一步支持了脂筏介导的过程。这些发现将有助于建立设计胆汁酸修饰的纳米药物的平台，并调节它们的转运以提高其抗癌疗效。
