Molecular Imaging Center, National Institute of Radiological Sciences, Anagawa, Chiba 263-8555, Japan.
Biomaterials. 2011 Sep;32(26):6052-8. doi: 10.1016/j.biomaterials.2011.04.076. Epub 2011 Jun 2.
Two-dimensional (2D) cell cultures are essential for drug development and tumor research. However, the limitations of 2D cultures are widely recognized, and a better technique is needed. Recent studies have indicated that a strong physical contact between cells and 2D substrates induces cellular characteristics that differ from those of tumors growing in vivo. 3D cell cultures using various substrates are then developing; nevertheless, conventional approaches have failed in maintenance of cellular proliferation and viability, uniformity, reproducibility, and/or simplicity of these assays. Here, we developed a 3D culture system with inorganic nanoscale scaffolding using nanoimprinting technology (nano-culture plates), which reproduced the characteristics of tumor cells growing in vivo. Diminished cell-to-substrate physical contact facilitated spontaneous tumor cell migration, intercellular adhesion, and multi-cellular 3D-spheroid formation while maintaining cellular proliferation and viability. The resulting multi-cellular spheroids formed hypoxic core regions similar to tumors growing in vivo. This technology allows creating uniform and highly-reproducible 3D cultures, which is easily applicable for microscopic and spectrophotometric assays, which can be used for high-throughput/high-content screening of anticancer drugs and should accelerate discovery of more effective anticancer therapies.
二维（2D）细胞培养对于药物开发和肿瘤研究至关重要。然而，2D 培养的局限性已得到广泛认可，因此需要更好的技术。最近的研究表明，细胞与 2D 基质之间的强烈物理接触会诱导出与体内生长的肿瘤不同的细胞特征。然后，正在开发使用各种基质的 3D 细胞培养；然而，传统方法在维持细胞增殖和活力、均匀性、重现性和/或这些测定的简单性方面都失败了。在这里，我们使用纳米压印技术（纳米培养板）开发了一种具有无机纳米尺度支架的 3D 培养系统，该系统再现了体内生长的肿瘤细胞的特征。减少细胞与基质的物理接触促进了肿瘤细胞的自发迁移、细胞间黏附和多细胞 3D 球体的形成，同时保持了细胞的增殖和活力。由此产生的多细胞球体形成了类似于体内生长的肿瘤的缺氧核心区域。该技术允许创建均匀且高度重现的 3D 培养物，非常适用于显微镜和分光光度测定，可用于高通量/高内涵筛选抗癌药物，并应加速发现更有效的抗癌疗法。
