Xu Xian, Sabanayagam Chandran R, Harrington Daniel A, Farach-Carson Mary C, Jia Xinqiao
Department of Materials Science and Engineering, University of Delaware, Newark, DE 19716, USA.
Delaware Biotechnology Institute, University of Delaware, Newark, DE 19711, USA.
Biomaterials. 2014 Mar;35(10):3319-30. doi: 10.1016/j.biomaterials.2013.12.080. Epub 2014 Jan 18.
Three-dimensional (3D) tissue-engineered tumor models have the potential to bridge the gap between monolayer cultures and patient-derived xenografts for the testing of nanoparticle (NP)-based cancer therapeutics. In this study, a hydrogel-derived prostate cancer (PCa) model was developed for the in vitro evaluation of doxorubicin (Dox)-loaded polymer NPs (Dox-NPs). The hydrogels were synthesized using chemically modified hyaluronic acid (HA) carrying acrylate groups (HA-AC) or reactive thiols (HA-SH). The crosslinked hydrogel networks exhibited an estimated pore size of 70-100 nm, similar to the spacing of the extracellular matrices (ECM) surrounding tumor tissues. LNCaP PCa cells entrapped in the HA matrices formed distinct tumor-like multicellular aggregates with an average diameter of 50 μm after 7 days of culture. Compared to cells grown on two-dimensional (2D) tissue culture plates, cells from the engineered tumoroids expressed significantly higher levels of multidrug resistance (MDR) proteins, including multidrug resistance protein 1 (MRP1) and lung resistance-related protein (LRP), both at the mRNA and the protein levels. Separately, Dox-NPs with an average diameter of 54 ± 1 nm were prepared from amphiphilic block copolymers based on poly(ethylene glycol) (PEG) and poly(ε-caprolactone) (PCL) bearing pendant cyclic ketals. Dox-NPs were able to diffuse through the hydrogel matrices, penetrate into the tumoroid and be internalized by LNCaP PCa cells through caveolae-mediated endocytosis and macropinocytosis pathways. Compared to 2D cultures, LNCaP PCa cells cultured as multicellular aggregates in HA hydrogel were more resistant to Dox and Dox-NPs treatments. Moreover, the NP-based Dox formulation could bypass the drug efflux function of MRP1, thereby partially reversing the resistance to free Dox in 3D cultures. Overall, the engineered tumor model has the potential to provide predictable results on the efficacy of NP-based cancer therapeutics.
三维（3D）组织工程肿瘤模型有潜力弥合单层培养与患者来源异种移植之间的差距，用于测试基于纳米颗粒（NP）的癌症治疗方法。在本研究中，开发了一种水凝胶衍生的前列腺癌（PCa）模型，用于体外评估负载阿霉素（Dox）的聚合物纳米颗粒（Dox-NPs）。使用带有丙烯酸酯基团（HA-AC）或活性硫醇（HA-SH）的化学修饰透明质酸（HA）合成水凝胶。交联的水凝胶网络显示估计孔径为70-100nm，类似于肿瘤组织周围细胞外基质（ECM）的间距。包埋在HA基质中的LNCaP PCa细胞在培养7天后形成平均直径为50μm的明显肿瘤样多细胞聚集体。与在二维（2D）组织培养板上生长的细胞相比，来自工程化类肿瘤的细胞在mRNA和蛋白质水平上均表达显著更高水平的多药耐药（MDR）蛋白，包括多药耐药蛋白1（MRP1）和肺耐药相关蛋白（LRP）。另外，基于聚乙二醇（PEG）和带有侧链环状缩酮的聚（ε-己内酯）（PCL）的两亲性嵌段共聚物制备了平均直径为54±1nm的Dox-NPs。Dox-NPs能够扩散通过水凝胶基质，渗透到类肿瘤中，并通过小窝介导的内吞作用和巨胞饮作用途径被LNCaP PCa细胞内化。与2D培养相比，在HA水凝胶中作为多细胞聚集体培养的LNCaP PCa细胞对Dox和Dox-NPs处理更具抗性。此外，基于NP的Dox制剂可以绕过MRP1的药物外排功能，从而部分逆转3D培养中对游离Dox的抗性。总体而言，工程化肿瘤模型有潜力为基于NP的癌症治疗方法的疗效提供可预测的结果。
