Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Sichuan Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu 610041, China.
J Control Release. 2020 May 10;321:71-83. doi: 10.1016/j.jconrel.2020.02.010. Epub 2020 Feb 5.
Oxidative-stress defense system stands for the vulnerability of tumor cells because of the stronger oxidative stress existing in tumor sites. TRPA-1 has been found to be overexpressed in various tumors, related to the tumor proliferation and metastasis, and promote reactive oxygen species (ROS) and chemotherapy tolerance through Ca-dependent anti-apoptotic pathway in recent studies, which provides a new anti-tumor approach to target oxidative-stress defense system. However, there are few studies on the mechanisms of TRPA-1 inhibition increasing the effectiveness of chemotherapy and inhibiting tumor metastasis. Here, in order to deliver drugs to the deep tumor where is full of stronger oxidative stress, a dual receptors-targeting and size-switchable "cluster bomb" co-loading doxorubicine (DOX) and TRPA-1 inhibitor AP-18 (DA-tMN) was designed. DSPE-PEG2000 micelles (M, ~10 nm) were connected to the master core of hyaluronic acid nanogels (N, ~100 nm) to realize HAase-responsive size-switchable and acquired targeting characteristics. Besides, tumor homing peptide tLyP-1 (t) was modified on the surface of micelles to further increase tumor accumulation. Our study showed that tLyP-1 modification enhanced tumor-targeting delivery of tLyP-1-modified micelles @ nanogels (tMN) in vitro and in vivo. Then, HAase responsive nanogel core realized the deep penetration of tMN in 4 T1 3D tumor spheres models and 4 T1 tumor-bearing mice models. In vitro anti-tumor and anti-metastasis mechanism studies indicated that AP-18 increased the sensitivity of tumor cells to DOX by inhibiting Ca influx and AKT phosphorylation caused by DOX. Compared with DOX-loaded tLyP-1-modified micelles @ nanogels (D-tMN), DA-tMN had the enhanced anti-tumor and anti-metastasis effect in vitro and vivo. Furthermore, the further anti-metastasis mechanism studies showed that TRPA-1 inhibition downregulate the expression of N-cadherin and vimentin and upregulate the expression of E-cadherin, which suggested that metastases inhibition caused by TRPA-1 inhibition may be related to the inhibition of epithelial-mesenchymal transition (EMT) process.
氧化应激防御系统代表了肿瘤细胞的脆弱性，因为肿瘤部位存在更强的氧化应激。最近的研究发现，TRPA-1 在各种肿瘤中过度表达，与肿瘤增殖和转移有关，并通过 Ca 依赖性抗细胞凋亡途径促进活性氧（ROS）和化疗耐药性，为靶向氧化应激防御系统提供了一种新的抗肿瘤方法。然而，关于 TRPA-1 抑制增加化疗效果和抑制肿瘤转移的机制研究较少。在这里，为了将药物递送到富含更强氧化应激的深部肿瘤中，设计了一种双重受体靶向和大小可切换的“集束炸弹”共载多柔比星（DOX）和 TRPA-1 抑制剂 AP-18（DA-tMN）。DSPE-PEG2000 胶束（M，10nm）连接到透明质酸纳米凝胶的主核（N，100nm）上，以实现 HAase 响应的大小可切换和获得靶向特性。此外，肿瘤归巢肽 tLyP-1（t）修饰在胶束表面，进一步增加了肿瘤的积累。我们的研究表明，tLyP-1 修饰增强了 tLyP-1 修饰的胶束@纳米凝胶（tMN）在体外和体内的肿瘤靶向递药。然后，HAase 响应的纳米凝胶核实现在 4T1 3D 肿瘤球体模型和 4T1 荷瘤小鼠模型中的深层渗透。体外抗肿瘤和抗转移机制研究表明，AP-18 通过抑制 DOX 引起的 Ca 内流和 AKT 磷酸化，增加了肿瘤细胞对 DOX 的敏感性。与 DOX 负载的 tLyP-1 修饰的胶束@纳米凝胶（D-tMN）相比，DA-tMN 在体外和体内具有增强的抗肿瘤和抗转移作用。此外，进一步的抗转移机制研究表明，TRPA-1 抑制下调 N-钙粘蛋白和波形蛋白的表达，上调 E-钙粘蛋白的表达，提示 TRPA-1 抑制引起的转移抑制可能与抑制上皮-间充质转化（EMT）过程有关。
