Cancer stem cells (CSCs) are considered to be responsible for recurrence, metastasis, and resistance to treatment in many types of cancers; therefore, new treatment strategies targeting CSCs are attracting attention. In this study, we fabricated a polyethylene glycol-tagged microwell device that enabled spheroid formation from human oral squamous carcinoma cells. HSC-3 and Ca9-22 cells cultured in the microwell device aggregated and generated a single spheroid per well within 24–48 h. The circular shape and smooth surface of spheroids were maintained for up to five days, and most cells comprising the spheroids were Calcein AM-positive viable cells. Interestingly, the mRNA expression of CSC markers (Cd44,Oct4,Nanog, andSox2) were significantly higher in the spheroids than in the monolayer cultures. CSC marker-positive cells were observed throughout the spheroids. Moreover, resistance to cisplatin was enhanced in spheroid-cultured cells compared to that in the monolayer-cultured cells. Furthermore, some CSC marker genes were upregulated in HSC-3 and Ca9-22 cells that were outgrown from spheroids. In xenograft model, the tumor growth in the spheroid implantation group was comparable to that in the monolayer culture group. These results suggest that our spheroid culture system may be a high-throughput tool for producing uniform CSCs in large numbers from oral cancer cells.
癌症干细胞被认为是导致多种癌症复发、转移及治疗抵抗的关键因素，因此针对癌症干细胞的新型治疗策略正受到广泛关注。本研究构建了一种聚乙二醇标记的微孔装置，能够使人源性口腔鳞状细胞癌细胞形成球体。在微孔装置中培养的HSC-3和Ca9-22细胞在24-48小时内聚集并在每个微孔中形成单个球体。这些球体保持圆形结构及光滑表面长达五天，且组成球体的大多数细胞为钙黄绿素AM染色阳性的活细胞。值得注意的是，球体中癌症干细胞标志物（Cd44、Oct4、Nanog和Sox2）的mRNA表达水平显著高于单层培养细胞。癌症干细胞标志物阳性细胞均匀分布于整个球体结构中。与单层培养细胞相比，球体培养细胞对顺铂的耐药性显著增强。此外，从球体中重新贴壁生长的HSC-3和Ca9-22细胞中，部分癌症干细胞标志基因表达出现上调。在异种移植模型中，球体移植组的肿瘤生长情况与单层培养移植组相当。这些结果表明，本研究建立的球体培养系统可能成为从口腔癌细胞中大规模、高通量制备均质化癌症干细胞的有效工具。
肿瘤(癌症)患者之家