Colorado State University, School of Biomedical Engineering (K.P.C., S.W., D.L.G.) and Department of Clinical Sciences (D.L.G., J.W.C.), Colorado State University, Fort Collins, Colorado; University of Colorado Cancer Center, Anschutz Medical Campus, Aurora, Colorado (D.L.G.); and University of Akron, Department of Chemistry, Akron, Ohio (Y.P.)
Colorado State University, School of Biomedical Engineering (K.P.C., S.W., D.L.G.) and Department of Clinical Sciences (D.L.G., J.W.C.), Colorado State University, Fort Collins, Colorado; University of Colorado Cancer Center, Anschutz Medical Campus, Aurora, Colorado (D.L.G.); and University of Akron, Department of Chemistry, Akron, Ohio (Y.P.).
J Pharmacol Exp Ther. 2021 Feb;376(2):294-305. doi: 10.1124/jpet.120.000309. Epub 2020 Nov 10.
Lysosomes act as a cellular drug sink for weakly basic, lipophilic (lysosomotropic) xenobiotics, with many instances of lysosomal trapping associated with multiple drug resistance. Lysosomotropic agents have also been shown to activate master lysosomal biogenesis transcription factor EB (TFEB) and ultimately lysosomal biogenesis. We investigated the role of lysosomal biogenesis in the disposition of hydroxychloroquine (HCQ), a hallmark lysosomotropic agent, and observed that modulating the lysosomal volume of human breast cancer cell lines can account for differences in disposition of HCQ. Through use of an in vitro pharmacokinetic (PK) model, we characterized total cellular uptake of HCQ within the duration of static equilibrium (1 hour), as well as extended exposure to HCQ that is subject to dynamic equilibrium (>1 hour), wherein HCQ increases the size of the lysosomal compartment through swelling and TFEB-induced lysosomal biogenesis. In addition, we observe that pretreatment of cell lines with TFEB-activating agent Torin1 contributed to an increase of whole-cell HCQ concentrations by 1.4- to 1.6-fold, which were also characterized by the in vitro PK model. This investigation into the role of lysosomal volume dynamics in lysosomotropic drug disposition, including the ability of HCQ to modify its own disposition, advances our understanding of how chemically similar agents may distribute on the cellular level and examines a key area of lysosomal-mediated multiple drug resistance and drug-drug interaction. SIGNIFICANCE STATEMENT: Hydroxychloroquine is able to modulate its own cellular pharmacokinetic uptake by increasing the cellular lysosomal volume fraction through activation of lysosomal biogenesis master transcription factor EB and through lysosomal swelling. This concept can be applied to many other lysosomotropic drugs that activate transcription factor EB, such as doxorubicin and other tyrosine kinase inhibitor drugs, as these drugs may actively increase their own sequestration within the lysosome to further exacerbate multiple drug resistance and lead to potential acquired resistance.
溶酶体作为细胞内的药物储存库，可容纳弱碱性、亲脂性（溶酶体靶向）的外来化合物，许多溶酶体捕获的实例与多药耐药性有关。溶酶体靶向剂也已被证明可以激活主溶酶体生物发生转录因子 EB（TFEB），并最终促进溶酶体生物发生。我们研究了溶酶体生物发生在羟氯喹（HCQ）处置中的作用，HCQ 是一种标志性的溶酶体靶向剂，观察到调节人乳腺癌细胞系的溶酶体体积可以解释 HCQ 处置的差异。通过使用体外药代动力学（PK）模型，我们在静态平衡（1 小时）的持续时间内描述了 HCQ 在细胞内的总摄取，以及对 HCQ 的扩展暴露，HCQ 通过肿胀和 TFEB 诱导的溶酶体生物发生来增加溶酶体隔室的大小。此外，我们观察到用 TFEB 激活剂 Torin1 预处理细胞系可使全细胞 HCQ 浓度增加 1.4-1.6 倍，这也可以通过体外 PK 模型来描述。这项关于溶酶体体积动力学在溶酶体靶向药物处置中的作用的研究，包括 HCQ 改变自身处置的能力，增进了我们对化学相似的药物如何在细胞水平上分布的理解，并研究了溶酶体介导的多药耐药性和药物相互作用的一个关键领域。意义声明：羟氯喹能够通过激活溶酶体生物发生的主转录因子 EB 并通过溶酶体肿胀来增加细胞溶酶体体积分数，从而调节自身的细胞 PK 摄取。这个概念可以应用于许多其他激活转录因子 EB 的溶酶体靶向药物，如多柔比星和其他酪氨酸激酶抑制剂药物，因为这些药物可能会主动增加自身在溶酶体中的隔离，从而进一步加剧多药耐药性，并导致潜在的获得性耐药。
