Ph.D. Program in Biomedical Engineering, Chang Gung University, Taoyuan, 33302, Taiwan.
Graduate Institute of Biochemical and Biomedical Engineering, Chang Gung University, No. 259, Wenhua 1st Rd., Guishan Dist., Taoyuan, 33302, Taiwan.
J Neurooncol. 2018 May;137(3):511-522. doi: 10.1007/s11060-018-2763-2. Epub 2018 Jan 22.
Glioblastoma (GBM) is the most malignant primary brain tumor and contains tumorigenic cancer stem cells (CSCs), which support the progression of tumor growth. The selection of CSCs and facilitation of the brain tumor niches may assist the development of novel therapeutics for GBM. Herein, hydrogel materials composed of agarose and hydroxypropyl methyl cellulose (HMC) in different concentrations were established and compared to emulate brain tumor niches and CSC microenvironments within a label-free system. Human GBM cell line, U-87 MG, was cultured on a series of HMC-agarose based culture system. Cell aggregation and spheroids formation were investigated after 4 days of culture, and 2.5% HMC-agarose based culture system demonstrated the largest spheroids number and size. Moreover, CD133 marker expression of GBM cells after 6 days of culture in 2.5% HMC-agarose based culture system was 60%, relatively higher than the control group at only 15%. Additionally, cells on 2.5% HMC-agarose based culture system show the highest chemoresistance, even at the high dose of 500 µM temozolomide for 72 h, the live cell ratio was still > 80%. Furthermore, the results also indicate that the expression of ABCG2 gene was up-regulated after culture in 2.5% HMC-agarose based culture system. Therefore, our results demonstrated that biomimetic brain tumor microenvironment may regulate GBM cells towards the CSC phenotype and expression of CSC characteristics. The microenvironment selection and spheroids formation in HMC-agarose based culture system may provide a label-free CSC selection strategy and drug testing model for future biomedical applications.
胶质母细胞瘤（GBM）是最恶性的原发性脑肿瘤，含有致瘤性癌症干细胞（CSC），这些细胞支持肿瘤生长的进展。CSC 的选择和脑肿瘤微环境的促进可能有助于开发针对 GBM 的新型治疗方法。在此，建立了由琼脂糖和羟丙基甲基纤维素（HMC）组成的水凝胶材料，并在无标记系统中比较了它们模拟脑肿瘤微环境和 CSC 微环境的能力。将人 GBM 细胞系 U-87 MG 培养在一系列基于 HMC-琼脂糖的培养系统上。培养 4 天后，研究了细胞聚集和球体形成情况，结果表明，基于 2.5% HMC-琼脂糖的培养系统具有最大的球体数量和大小。此外，在基于 2.5% HMC-琼脂糖的培养系统中培养 6 天后，GBM 细胞的 CD133 标志物表达率为 60%，相对高于对照组的 15%。此外，基于 2.5% HMC-琼脂糖的培养系统上的细胞表现出最高的化疗耐药性，即使在 500 μM 替莫唑胺的高剂量下孵育 72 小时后，活细胞比例仍>80%。此外，结果还表明，在基于 2.5% HMC-琼脂糖的培养系统中培养后，ABCG2 基因的表达上调。因此，我们的研究结果表明，仿生脑肿瘤微环境可能会使 GBM 细胞向 CSC 表型和 CSC 特征表达转变。在 HMC-琼脂糖为基础的培养系统中进行微环境选择和球体形成，可能为未来的生物医学应用提供一种无标记的 CSC 选择策略和药物测试模型。
