College of Pharmacy, Seoul National University, Seoul 08826, South Korea.
College of Pharmacy, Seoul National University, Seoul 08826, South Korea.
Acta Biomater. 2022 Jan 15;138:228-239. doi: 10.1016/j.actbio.2021.10.031. Epub 2021 Oct 28.
Drug-resistant cancer spheroids were fabricated by three-dimensional (3D) bioprinting for the quantitative evaluation of drug resistance of cancer cells, which is a very important issue in cancer treatment. Cancer spheroids have received great attention as a powerful in vitro model to replace animal experiments because of their ability to mimic the tumor microenvironment. In this work, the extrusion printing of gelatin-alginate hydrogel containing MCF-7 breast cancer stem cells successfully provided 3D growth of many single drug-resistant breast cancer spheroids in a cost-effective 3D-printed mini-well dish. The drug-resistant MCF-7 breast cancer spheroids were able to maintain their drug-resistant phenotype of CD44/CD24/ALDH1 in the gelatin-alginate media during 3D culture and exhibited higher expression levels of drug resistance markers, such as GRP78 chaperon and ABCG2 transporter, than bulk MCF-7 breast cancer spheroids. Furthermore, the effective concentration 50 (EC) values for apoptotic and necrotic spheroid death could be directly determined from the 3D printed-gelatin-alginate gel matrix based on in situ 3D fluorescence imaging of cancer spheroids located out of the focal point and on the focal point. The EC values of anti-tumor agents (camptothecin and paclitaxel) for apoptotic and necrotic drug-resistant cancer spheroid death were higher than those for bulk cancer spheroid death, indicating a greater drug resistance. STATEMENT OF SIGNIFICANCE: This study proposed a novel 3D bioprinting-based drug screening model, to quantitatively evaluate the efficacy of anticancer drugs using drug-resistant MCF-7 breast cancer spheroids formed within a 3D-printed hydrogel. Quantitative determination of anticancer drug efficacy using EC, which is extremely important in drug discovery, was achieved by 3D printing that enables concurrent growth of many single spheroids efficiently. This study verified whether drug-resistant cancer spheroids grown within 3D-printed gelatin-alginate hydrogel could maintain and present drug resistance. Also, the EC values of the apoptotic and necrotic cell deaths were directly acquired in 3D-embedded spheroids based on in situ fluorescence imaging. This platform provides a single-step straightforward strategy to cultivate and characterize drug-resistant spheroids to facilitate anticancer drug screening.
耐药性癌细胞球状体通过三维（3D）生物打印制造，用于定量评估癌细胞的耐药性，这是癌症治疗中的一个非常重要的问题。癌细胞球状体因其能够模拟肿瘤微环境而受到极大关注，是替代动物实验的强大体外模型。在这项工作中，成功地通过挤出打印含有 MCF-7 乳腺癌干细胞的明胶-海藻酸盐水凝胶，在经济高效的 3D 打印微型培养皿中提供了许多单个耐药性乳腺癌球状体的 3D 生长。耐药性 MCF-7 乳腺癌球状体能够在 3D 培养过程中保持其在明胶-海藻酸盐介质中的 CD44/CD24/ALDH1 耐药表型，并表现出更高水平的耐药性标志物，如 GRP78 伴侣和 ABCG2 转运体，比大块 MCF-7 乳腺癌球状体高。此外，通过对位于焦点外和焦点内的癌细胞球状体的原位 3D 荧光成像，可以直接从 3D 打印的明胶-海藻酸盐凝胶基质中确定凋亡和坏死球状体死亡的有效浓度 50（EC）值。抗癌剂（喜树碱和紫杉醇）对凋亡和坏死耐药性癌细胞球状体死亡的 EC 值高于对大块癌细胞球状体死亡的 EC 值，表明耐药性更大。
这项研究提出了一种新的基于 3D 生物打印的药物筛选模型，使用在 3D 打印水凝胶中形成的耐药性 MCF-7 乳腺癌球状体定量评估抗癌药物的功效。通过 3D 打印实现了 EC 的抗癌药物功效的定量测定，这在药物发现中非常重要，3D 打印能够高效地同时生长许多单个球状体。本研究验证了在 3D 打印的明胶-海藻酸盐水凝胶中生长的耐药性癌细胞球状体是否能够维持和表现出耐药性。此外，还基于原位荧光成像直接从 3D 嵌入的球状体中获得了凋亡和坏死细胞死亡的 EC 值。该平台提供了一种简单的一步策略，用于培养和表征耐药性球状体，以促进抗癌药物筛选。
